Search results for: non uniform laminated structures
1513 Modeling and Behavior of Structural Walls
Authors: Salima Djehaichia, Rachid Lassoued
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Reinforced concrete structural walls are very efficient elements for protecting buildings against excessive early damage and against collapse under earthquake actions. It is therefore of interest to develop a numerical model which simulates the typical behavior of these units, this paper presents and describes different modeling techniques that have been used by researchers and their advantages and limitations mentioned. The earthquake of Boumerdes in 2003 has demonstrated the fragility of structures and total neglect of sismique design rules in the realization of old buildings. Significant damage and destruction of buildings caused by this earthquake are not due to the choice of type of material, but the design and the study does not congruent with seismic code requirements and bad quality of materials. For idealizing the failure of rules, a parametric study focuses on: low rate of reinforcements, type of reinforcement, resistance moderate of concrete. As an application the modeling strategy based on finite elements combined with a discretization of wall more solicited by successive thin layers. The estimated performance level achieved during a seismic action is obtained from capacity curves under incrementally increasing loads. Using a pushover analysis, a characteristic non linear force-displacement relationship can be determined. The results of numeric model are confronted with those of Algerian Para seismic Rules (RPA) in force have allowed the determination of profits in terms of displacement, shearing action, ductility.Keywords: modeling, old building, pushover analysis, structural walls
Procedia PDF Downloads 2461512 Impact of Electric Field on the Optical Properties of Hydrophilic Quantum Dots
Authors: Valentina V. Goftman, Vladislav A. Pankratov, Alexey V. Markin, Tangi Aubert, Zeger Hens, Sarah De Saeger, Irina Yu. Goryacheva
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The most important requirements for biochemical applicability of quantum dots (QDs) are: 1) the surface cap should render intact or improved optical properties; 2) mono-dispersion and good stability in aqueous phase in a wide range of pH and ionic strength values; 3) presence of functional groups, available for bioconjugation; 4) minimal impact from the environment on the QDs’ properties and, vice versa, minimal influence of the QDs’ components on the environment; and 5) stability against chemical/biochemical/physical influence. The latter is especially important for in vitro and in vivo applications. For example, some physical intracellular delivery strategies (e.g., electroporation) imply a rapid high-voltage electric field impulse in order to temporarily generate hydrophilic pores in the cell plasma membrane, necessary for the passive transportation of QDs into the cell. In this regard, it is interesting to investigate how different capping layers, which can provide high stability and sufficient fluorescent properties of QDs in a water solution, behave under these abnormal conditions. In this contribution, hydrophobic core-shell CdSe/CdS/CdZnS/ZnS QDs (λem=600 nm), produced by means of the Successive Ion Layer Adsorption and Reaction (SILAR) technique, were transferred to a water solution using two of the most commonly used methods: (i) encapsulation in an amphiphilic brush polymer based on poly(maleic anhydride-alt-1-octadecene) (PMAO) modified with polyethylene glycol (PEG) chains and (ii) silica covering. Polymer encapsulation preserves the initial ligands on the QDs’ surface owing to the hydrophobic attraction between the hydrophobic groups of the amphiphilic molecules and the surface hydrophobic groups of the QDs. This covering process allows maintaining the initial fluorescent properties, but it leads to a considerable increase of the QDs’ size. However, covering with a silica shell, by means of the reverse microemulsion method, allows maintaining both size and fluorescent properties of the initial QDs. The obtained water solutions of polymer covered and silica-coated QDs in three different concentrations were exposed to a low-voltage electric field for a short time and the fluorescent properties were investigated. It is shown that the PMAO-PEG polymer acquires some additional charges in the presence of the electric field, which causes repulsion between the polymer and the QDs’ surface. This process destroys the homogeneity of the whole amphiphilic shell and it dramatically decreases the fluorescent properties (dropping to 10% from its initial value) because of the direct contact of the QDs with the strongly oxidative environment (water). In contrast, a silica shell possesses dielectric properties which allow retaining 90% of its initial fluorescence intensity, even after a longer electric impact. Thus, silica shells are clearly a preferable covering for bio-application of QDs, because – besides the high uniform morphology, controlled size and biocompatibility – it allows protecting QDs from oxidation, even under the influence of an electric field.Keywords: electric field, polymer coating, quantum dots, silica covering, stability
Procedia PDF Downloads 4581511 Oxyhydrogen Gas (HHO) as Replacement to Gasoline Fuel
Authors: Rishabh Pandey, Umang Kumar Yadav
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In today’s era of technological advancement, we come across incalculable innovations, almost every day. No doubt that the society has developed a lot in learning and technology, but we should also take into account the problems and inflictions that are occurring. Focusing on the petroleum sector a trending global concern is toward lowering fuel consumption and emissions. It is well known that gasoline is non-renewable source of energy and its burning produces harmful emissions which are adversely affecting the environment, such issues are motivating us to seek alternative solutions that would not require much modification in engine design and help us come out with an outcome. Keeping in mind the importance of environment and human race, we present a factious idea of use of oxyhydrogen gas or HHO gas in place of gasoline in the vehicles and petroleum industry. This technology is prospering, highly efficient, could be used economically and safe, and it will be responsible for changing the future of oil and gas sector in accordance with protection to the environment. In the coming future, we will check the compatibility of HHO generator with fuel engine for production of oxyhydrogen gas with use of water and effect of introducing HHO gas to the combustion on both thermal efficiency and specific fuel consumption. We will also work on the comparison of HHO gas and commercially available gasoline fuel in support of their chemical structures; ignition rate; octane rating; knocking properties; storage; transportation and cost effectiveness and it is trusted that use of HHO gas will be ecofriendly as no harmful emissions are produced, rather the only emission is water. Additionally, this paper will include the use of HHO cell in fuel engines and challenges faced in installing it in the current period and provide effective solutions for the same.Keywords: fuel, gas, generator, water
Procedia PDF Downloads 3271510 A Conundrum of Teachability and Learnability of Deaf Adult English as Second Language Learners in Pakistani Mainstream Classrooms: Integration or Elimination
Authors: Amnah Moghees, Saima Abbas Dar, Muniba Saeed
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Teaching a second language to deaf learners has always been a challenge in Pakistan. Different approaches and strategies have been followed, but they have been resulted into partial or complete failure. The study aims to investigate the language problems faced by adult deaf learners of English as second language in mainstream classrooms. Moreover, the study also determines the factors which are very much involved in language teaching and learning in mainstream classes. To investigate the language problems, data will be collected through writing samples of ten deaf adult learners and ten normal ESL learners of the same class; whereas, observation in inclusive language teaching classrooms and interviews from five ESL teachers in inclusive classes will be conducted to know the factors which are directly or indirectly involved in inclusive language education. Keeping in view this study, qualitative research paradigm will be applied to analyse the corpus. The study figures out that deaf ESL learners face severe language issues such as; odd sentence structures, subject and verb agreement violation, misappropriation of verb forms and tenses as compared to normal ESL learners. The study also predicts that in mainstream classrooms there are multiple factors which are affecting the smoothness of teaching and learning procedure; role of mediator, level of deaf learners, empathy of normal learners towards deaf learners and language teacher’s training.Keywords: deaf English language learner, empathy, mainstream classrooms, previous language knowledge of learners, role of mediator, language teachers' training
Procedia PDF Downloads 1661509 A Study on the Failure Modes of Steel Moment Frame in Post-Earthquake Fire Using Coupled Mechanical-Thermal Analysis
Authors: Ehsan Asgari, Meisam Afazeli, Nezhla Attarchian
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Post-earthquake fire is considered as a major threat in seismic areas. After an earthquake, fire is possible in structures. In this research, the effect of post-earthquake fire on steel moment frames with and without fireproofing coating is investigated. For this purpose, finite element method is employed. For the verification of finite element results, the results of an experimental study carried out by previous researchers are used, and the predicted FE results are compared with the test results, and good agreement is observed. After ensuring the accuracy of the predictions of finite element models, the effect of post-earthquake fire on the frames is investigated taking into account the parameters including the presence or absence of fire protection, frame design assumptions, earthquake type and different fire scenario. Ordinary fire and post-earthquake fire effect on the frames is also studied. The plastic hinges induced by earthquake in the structure are determined in the beam to the column connection and in panel zone. These areas should be accurately considered when providing fireproofing coatings. The results of the study show that the occurrence of fire beside corner columns is the most damaging scenario that results in progressive collapse of structure. It was also concluded that the behavior of structure in fire after a strong ground motion is significantly different from that in a normal fire.Keywords: post earthquake fire, moment frame, finite element simulation, coupled temperature-displacement analysis, fire scenario
Procedia PDF Downloads 1541508 Optical Design and Modeling of Micro Light-Emitting Diodes for Display Applications
Authors: Chaya B. M., C. Dhanush, Inti Sai Srikar, Akula Pavan Parvatalu, Chirag Gowda R
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Recently, there has been a lot of interest in µ-LED technology because of its exceptional qualities, including auto emission, high visibility, low consumption of power, rapid response and longevity. Light-emitting diodes (LED) using III-nitride, such as lighting sources, visible light communication (VLC) devices, and high-power devices, are finding increasing use as miniaturization technology advances. The use of micro-LED displays in place of traditional display technologies like liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs) is one of the most prominent recent advances, which may even represent the next generation of displays. The development of fully integrated, multifunctional devices and the incorporation of extra capabilities into micro-LED displays, such as sensing, light detection, and solar cells, are the pillars of advanced technology. Due to the wide range of applications for micro-LED technology, the effectiveness and dependability of these devices in numerous harsh conditions are becoming increasingly important. Enough research has been conducted to overcome the under-effectiveness of micro-LED devices. In this paper, different Micro LED design structures are proposed in order to achieve optimized optical properties. In order to attain improved external quantum efficiency (EQE), devices' light extraction efficiency (LEE) has also been boosted.Keywords: finite difference time domain, light out coupling efficiency, far field intensity, power density, quantum efficiency, flat panel displays
Procedia PDF Downloads 791507 Disaster Management and Resilience: A Conceptual Synthesis of Local
Authors: Oshienemen Albert, Dilanthi Amaratunga, Richard Haigh
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Globally, disasters of any form can affect the environment, built environment, the waterways, societies, nations and communities in diverse areas. The such impacts could cut across, economic loss, social setting, cultural and livelihood structures of affected population. Thus, the raise of disaster impacts across developing nations are alarming with decades impact due to the lack of hard and soft infrastructural development across communities, inconsistency in the governmental policy and implementation, making it difficult for disaster affected communities to bounce back when necessary, especially in Nigeria. The Nigeria disasters, especially oil spillages have affected diverse communities across the Niger Delta region for decades with little or nothing as external support for the broken livelihood structure, cultural and economic damages of the people. Though, in the spirit of contribution to the communities affected by oil spill and negative consequence of petroleum production, the federal government at different times established some impressionistic bodies and agencies to oversee the affairs of the region as with regards to oil spillages and development. Thus, the agencies contributions are yet to manifest in practice. This amplifies the quest for the structural clarities of the management systems and the resilience’s of the communities, to better equip the communities for any such disaster. Therefore, the study sets to explore the Nigerian disaster management systems and resilience concept at local community level. Thus, desk-based approach and interviews are employed for the synthesis while, drawing conclusion and recommendations.Keywords: disaster, community, management, resilience
Procedia PDF Downloads 1851506 Evaluation of Prevalence of the Types of Thyroid Disorders Using Ultrasound and Pathology of One-Humped Camel in Iran: Camelus dromedarius
Authors: M. Yadegari
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The thyroid gland is the largest classic endocrine organ that effects many organs of the body and plays a significant role in the process of Metabolism in animals. The aim of this study was to investigate the prevalence of thyroid disorders diagnosed by ultrasound and microscopic Lesions of the thyroid during the slaughter of apparently healthy One Humped Camels (Camelus dromedarius) in Iran. Randomly, 520 male camels (With an age range of 4 to 8 years), were studied in 2012 to 2013. The Camels’ thyroid glands were evaluated by sonographic examination. In both longitudinal and transverse view and then tissue sections were provide and stained with H & E and finally examined by light microscopy. The results obtained indicated the following: hyperplastic goiter (21%), degenerative changes (12%), follicular cysts (8%), follicular atrophy (4%), nodular hyperplasia (3%), adenoma (1%), carcinoma (1%) and simple goiter colloid (1%). Ultrasound evaluation of thyroid gland in adenoma and carcinoma showed enlargement and irregular of the gland, decreased echogenicity, and the heterogeneous thyroid parenchyma. Also, in follicular cysts were observed in the enlarged gland with no echo structures of different sizes and decreased echogenicity as a local or general. In nodular hyperplasia, increase echogenicity and heterogeneous parenchymal were seen. These findings suggest the use of Ultrasound as a screening test in the diagnosis of complications of thyroid disorders. Pathology also to be used for the diagnosis of thyroid problems and other side effects.Keywords: thyroid gland, one humped camel, sonography, pathology
Procedia PDF Downloads 5081505 Examining the Links between Established Principles, Iranian Teachers' Perceptions of Reading Comprehension, and Their Actual Practice in English for Specific Purposes Courses
Authors: Zahra Alimorad
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There is a strong belief that language teachers' actual practices in the classroom context are largely determined by the underlying perceptions they hold about the nature of language and language learning. That being so, it can be envisaged that teaching procedures of ESP (English for Specific Purposes) teachers teaching reading comprehension will mainly be driven by their perceptions about the nature of reading. To examine this issue, four Iranian university professors holding Ph.D. in either TEFL (Teaching English as a Foreign Language) or English Literature who were teaching English to Engineering and Sciences students were recruited to participate in this study. To collect the necessary data, classroom observations and follow-up semi-structured interviews were used. Furthermore, the materials utilized by the teachers such as textbooks, syllabuses, and tests were also examined. Although it can be argued that their perceptions were partially compatible with the established principles, results of the study pointed to a lack of congruence between these teachers' perceptions and their practices, on the one hand, and between the established principles and the practices, on the other. While the literature mostly supports a metacognitive-strategy approach to reading comprehension, the teachers were mainly adopting a skills-based approach to the teaching of reading. That is, they primarily focused on translation as the core activity in the classroom followed by reading aloud, defining words, and explaining grammatical structures. This divergence was partly attributed to the contextual constraints and partly to students' lack of motivation by the teachers.Keywords: English teachers, perceptions, practice, principles, reading comprehension
Procedia PDF Downloads 2621504 Quantitative Structure-Activity Relationship Analysis of Binding Affinity of a Series of Anti-Prion Compounds to Human Prion Protein
Authors: Strahinja Kovačević, Sanja Podunavac-Kuzmanović, Lidija Jevrić, Milica Karadžić
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The present study is based on the quantitative structure-activity relationship (QSAR) analysis of eighteen compounds with anti-prion activity. The structures and anti-prion activities (expressed in response units, RU%) of the analyzed compounds are taken from CHEMBL database. In the first step of analysis 85 molecular descriptors were calculated and based on them the hierarchical cluster analysis (HCA) and principal component analysis (PCA) were carried out in order to detect potential significant similarities or dissimilarities among the studied compounds. The calculated molecular descriptors were physicochemical, lipophilicity and ADMET (absorption, distribution, metabolism, excretion and toxicity) descriptors. The first stage of the QSAR analysis was simple linear regression modeling. It resulted in one acceptable model that correlates Henry's law constant with RU% units. The obtained 2D-QSAR model was validated by cross-validation as an internal validation method. The validation procedure confirmed the model’s quality and therefore it can be used for prediction of anti-prion activity. The next stage of the analysis of anti-prion activity will include 3D-QSAR and molecular docking approaches in order to select the most promising compounds in treatment of prion diseases. These results are the part of the project No. 114-451-268/2016-02 financially supported by the Provincial Secretariat for Science and Technological Development of AP Vojvodina.Keywords: anti-prion activity, chemometrics, molecular modeling, QSAR
Procedia PDF Downloads 3041503 River Offtake Management Using Mathematical Modelling Tool: A Case Study of the Gorai River, Bangladesh
Authors: Sarwat Jahan, Asker Rajin Rahman
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Management of offtake of any fluvial river is very sensitive in terms of long-term sustainability where the variation of water flow and sediment transport range are wide enough throughout a hydrological year. The Gorai River is a major distributary of the Ganges River in Bangladesh and is termed as a primary source of fresh water for the South-West part of the country. Every year, significant siltation of the Gorai offtake disconnects it from the Ganges during the dry season. As a result, the socio-economic and environmental condition of the downstream areas has been deteriorating for a few decades. To improve the overall situation of the Gorai offtake and its dependent areas, a study has been conducted by the Institute of Water Modelling, Bangladesh, in 2022. Using the mathematical morphological modeling tool MIKE 21C of DHI Water & Environment, Denmark, simulated results revealed the need for dredging/river training structures for offtake management at the Gorai offtake to ensure significant dry season flow towards the downstream. The dry season flow is found to increase significantly with the proposed river interventions, which also improves the environmental conditions in terms of salinity of the South-West zone of the country. This paper summarizes the primary findings of the analyzed results of the developed mathematical model for improving the existing condition of the Gorai River.Keywords: Gorai river, mathematical modelling, offtake, siltation, salinity
Procedia PDF Downloads 971502 Tunable Optoelectronic Properties of WS₂ by Local Strain Engineering and Folding
Authors: Ahmed Raza Khan
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Local-strain engineering is an exciting approach to tune the optoelectronic properties of materials and enhance the performance of devices. Two dimensional (2D) materials such as 2D transition metal dichalcogenides (TMDCs) are particularly well-suited for this purpose because they have high flexibility and can withstand high deformations before rupture. Wrinkles on thick TMDC layers have been reported to show the interesting photoluminescence enhancement due to bandgap modulation and funneling effect. However, the wrinkles in ultrathin TMDCs have not been investigated, because the wrinkles can easily fall down to form folds in these ultrathin layers of TMDCs. Here, we have achieved both wrinkle and fold nano-structures simultaneously on 1-3L WS₂ using a new fabrication technique. The comparable layer dependent reduction in surface potential is observed for both folded layers and corresponding perfect pack layers due to the dominant interlayer screening effect. The strains produced from the wrinkle nanostructures considerably vary semi conductive junction properties. Thermo-ionic modelling suggests that the strained (1.6%) wrinkles can lower the Schottky barrier height (SBH) by 20%. The photo-generated carriers would further significantly lower the SBH. These results present an important advance towards controlling the optoelectronic properties of atomically thin WS₂ using strain engineering, with important implications for practical device applications.Keywords: strain engineering, folding, WS₂, Kelvin probe force microscopy, KPFM, surface potential, photo current, layer dependence
Procedia PDF Downloads 1071501 Investigation of Crack Formation in Ordinary Reinforced Concrete Beams and in Beams Strengthened with Carbon Fiber Sheet: Theory and Experiment
Authors: Anton A. Bykov, Irina O. Glot, Igor N. Shardakov, Alexey P. Shestakov
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This paper presents the results of experimental and theoretical investigations of the mechanisms of crack formation in reinforced concrete beams subjected to quasi-static bending. The boundary-value problem has been formulated in the framework of brittle fracture mechanics and has been solved by using the finite-element method. Numerical simulation of the vibrations of an uncracked beam and a beam with cracks of different size serves to determine the pattern of changes in the spectrum of eigenfrequencies observed during crack evolution. Experiments were performed on the sequential quasistatic four-point bending of the beam leading to the formation of cracks in concrete. At each loading stage, the beam was subjected to an impulse load to induce vibrations. Two stages of cracking were detected. At the first stage the conservative process of deformation is realized. The second stage is an active cracking, which is marked by a sharp change in eingenfrequencies. The boundary of a transition from one stage to another is well registered. The vibration behavior was examined for the beams strengthened by carbon-fiber sheet before loading and at the intermediate stage of loading after the grouting of initial cracks. The obtained results show that the vibrodiagnostic approach is an effective tool for monitoring of cracking and for assessing the quality of measures aimed at strengthening concrete structures.Keywords: crack formation, experiment, mathematical modeling, reinforced concrete, vibrodiagnostics
Procedia PDF Downloads 3051500 Prediction of Marijuana Use among Iranian Early Youth: an Application of Integrative Model of Behavioral Prediction
Authors: Mehdi Mirzaei Alavijeh, Farzad Jalilian
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Background: Marijuana is the most widely used illicit drug worldwide, especially among adolescents and young adults, which can cause numerous complications. The aim of this study was to determine the pattern, motivation use, and factors related to marijuana use among Iranian youths based on the integrative model of behavioral prediction Methods: A cross-sectional study was conducted among 174 youths marijuana user in Kermanshah County and Isfahan County, during summer 2014 which was selected with the convenience sampling for participation in this study. A self-reporting questionnaire was applied for collecting data. Data were analyzed by SPSS version 21 using bivariate correlations and linear regression statistical tests. Results: The mean marijuana use of respondents was 4.60 times at during week [95% CI: 4.06, 5.15]. Linear regression statistical showed, the structures of integrative model of behavioral prediction accounted for 36% of the variation in the outcome measure of the marijuana use at during week (R2 = 36% & P < 0.001); and among them attitude, marijuana refuse, and subjective norms were a stronger predictors. Conclusion: Comprehensive health education and prevention programs need to emphasize on cognitive factors that predict youth’s health-related behaviors. Based on our findings it seems, designing educational and behavioral intervention for reducing positive belief about marijuana, marijuana self-efficacy refuse promotion and reduce subjective norms encourage marijuana use has an effective potential to protect youths marijuana use.Keywords: marijuana, youth, integrative model of behavioral prediction, Iran
Procedia PDF Downloads 5541499 Analysis of Rectangular Concrete-Filled Double Skin Tubular Short Columns with External Stainless Steel Tubes
Authors: Omnia F. Kharoob, Nashwa M. Yossef
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Concrete-filled double skin steel tubular (CFDST) columns could be utilized in structures such as bridges, high-rise buildings, viaducts, and electricity transmission towers due to its great structural performance. Alternatively, lean duplex stainless steel has recently gained significant interest for its high structural performance, similar corrosion resistance and lower cost compared to the austenitic steel grade. Hence, this paper presents the nonlinear finite element (FE) analysis, behaviour and design of rectangular outer lean duplex stainless steel (EN 1.4162) CFDST short columns under compression. All classes of the outer rectangular hollow section according to the depth-to-thickness (D/t) ratios were considered. The results showed that the axial ultimate strength of rectangular CFDST short columns increased linearly by increasing the concrete compressive strength, while it does not influence when changing the hollow ratios. Finally, the axial capacities were compared with the available design methods, and recommendations were conducted for the design strength of this type of column.Keywords: concrete-filled double skin columns, compressive strength, finite element analysis, lean duplex stainless steel, ultimate axial strength, short columns
Procedia PDF Downloads 3031498 Experimental Investigation to Produce an Optimum Mix Ratio of Micro-Concrete
Authors: Shofiq Ahmed, Rakibul Hassan, Raquib Ahsan
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Concrete is one of the basic elements of RCC structure and also the most crucial one. In recent years, a lot of researches have been conducted to develop special types of concrete for special purposes. Micro-concrete is one of them which has high compressive strength and is mainly used for retrofitting. Micro-concrete is a cementitious based composition formulated for use in repairs of areas where the concrete is damaged & the area is confined in movement making the placement of conventional concrete difficult. According to recent statistics, a large number of structures in the major cities of Bangladesh are vulnerable to collapse. Retrofitting may thus be required for a sustainable solution, and for this purpose, the utilization of micro-concrete can be considered as the most effective solution. For that reason, the aim of this study was to produce micro-concrete using indigenous materials in low cost. Following this aim, the experimental data were observed for five mix ratios with varied amount of cement, fine aggregate, coarse aggregate, water, and admixture. The investigation criteria were a compressive strength, tensile strength, slump and the cost of different mix ratios. Finally, for a mix ratio of 1:1:1.5, the compressive strength was achieved as 7820 psi indicating highest strength among all the samples with the reasonable tensile strength of 1215 psi. The slump of 6.9 inches was also found for this specimen indicating it’s high flowability and making it’s convenient to use as micro-concrete. Moreover, comparing with the cost of foreign products of micro-concrete, it was observed that foreign products were almost four to five times costlier than this local product.Keywords: indigenous, micro-concrete, retrofitting, vulnerable
Procedia PDF Downloads 3271497 Expression of Stance in Lower- and Upper- Level Students’ Writing in Business Administration at English-Medium University in Burundi
Authors: Clement Ndoricimpa
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The expression of stance is highly expected in writing at tertiary level. Through a selection of linguistic and rhetorical elements, writers express commitment, critical distance and build a critically discerning reader in texts. Despite many studies on patterns of stance in students’ academic writing, little may not be known about how English as a Foreign Language students learns to build a critically discerning reader in their texts. Therefore, this study examines patterns of stance in essays written by students majoring in business administration at English-medium University in Burundi as part of classroom assignments. It draws on systemic functional linguistics to analyze qualitatively and quantitatively the data. The quantitative analysis is used to identify the differences in frequency of stance patterns in the essays. The results show a significant difference in the use of boosters by lower- and upper-level students. Lower-level students’ writing contains more boosters and many idiosyncratic sentence structures than do upper-level students’ writing, and upper-level students’ essays contain more hedging and few grammatical mistakes than do lower-level students’ essays. No significant difference in the use of attitude markers and concessive and contrastive expressions. Students in lower- and upper-level do not use attitude markers and disclaimer markers appropriately and accurately. These findings suggest that students should be taught the use of stance patterns in academic writing.Keywords: academic writing, metadiscourse, stance, student corpora
Procedia PDF Downloads 1371496 Theoretical Study of Electronic Structure of Erbium (Er), Fermium (Fm), and Nobelium (No)
Authors: Saleh O. Allehabi, V. A. Dzubaa, V. V. Flambaum, Jiguang Li, A. V. Afanasjev, S. E. Agbemava
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Recently developed versions of the configuration method for open shells, configuration interaction with perturbation theory (CIPT), and configuration interaction with many-body perturbation theory (CI+MBPT) techniques are used to study the electronic structure of Er, Fm, and No atoms. Excitation energies of odd states connected to the even ground state by electric dipole transitions, the corresponding transition rates, isotope shift, hyperfine structure, ionization potentials, and static scalar polarizabilities are calculated. The way of extracting parameters of nuclear charge distribution beyond nuclear root mean square (RMS) radius, e.g., a parameter of quadrupole deformation β, is demonstrated. In nuclei with spin > 1/2, parameter β is extracted from the quadrupole hyperfine structure. With zero nuclear spin or spin 1/2, it is impossible since quadrupole zero, so a different method was developed. The measurements of at least two atomic transitions are needed to disentangle the contributions of the changes in deformation and nuclear RMS radius into field isotopic shift. This is important for testing nuclear theory and for searching for the hypothetical island of stability. Fm and No are heavy elements approaching the superheavy region, for which the experimental data are very poor, only seven lines for the Fm element and one line for the No element. Since Er and Fm have similar electronic structures, calculations for Er serve as a guide to the accuracy of the calculations. Twenty-eight new levels of Fm atom are reported.Keywords: atomic spectra, electronic transitions, isotope effect, electron correlation calculations for atoms
Procedia PDF Downloads 1551495 Study of White Salted Noodles Air Dehydration Assisted by Microwave as Compared to Conventional Air Dried Process
Authors: Chiun-C. R. Wang, I-Yu Chiu
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Drying is the most difficult and critical step to control in the dried salted noodles production. Microwave drying has the specific advantage of rapid and uniform heating due to the penetration of microwaves into the body of the product. Microwave-assisted facility offers a quick and energy saving method during food dehydration as compares to the conventional air-dried method for the noodle preparation. Recently, numerous studies in the rheological characteristics of pasta or spaghetti were carried out with microwave–assisted and conventional air driers and many agricultural products were dried successfully. There is very few research associated with the evaluation of physicochemical characteristics and cooking quality of microwave-assisted air dried salted noodles. The purposes of this study were to compare the difference between conventional air and microwave-assisted air drying method on the physicochemical properties and eating quality of rice bran noodles. Three different microwave power including 0.5 KW, 0.75 KW and 1.0 KW installing with 50℃ hot air were applied for dehydration of rice bran noodles in this study. Three proportion of rice bran ranging in 0-20% were incorporated into salted noodles processing. The appearance, optimum cooking time, cooking yield and losses, textural profiles analysis, and sensory evaluation of rice bran noodles were measured in this study. The results indicated that high power (1.0 KW) microwave facility caused partially burnt and porous on the surface of rice bran noodles. However, no significant difference of noodle was appeared on the surface of noodles between low power (0.5 KW) microwave-assisted salted noodles and control set. The optimum cooking time of noodles was decreased as higher power microwave was applied or higher proportion of rice bran was incorporated in the preparation of salted noodles. The higher proportion of rice bran (20%) or higher power of microwave-assisted dried noodles obtained the higher color intensity and the higher cooking losses as compared with conventional air dried noodles. Meanwhile, the higher power of microwave-assisted air dried noodles indicated the larger air cell inside the noodles and appeared little burnt stripe on the surface of noodles. The firmness of cooked rice bran noodles slightly decreased in the cooked noodles which were dried by high power microwave-assisted method. The shearing force, tensile strength, elasticity and texture profiles of cooked rice noodles decreased with the progress of the proportion of rice bran. The results of sensory evaluation indicated conventional dried noodles obtained the higher springiness, cohesiveness and overall acceptability of cooked noodles than high power (1.0 KW) microwave-assisted dried noodles. However, low power (0.5 KW) microwave-assisted dried noodles showed the comparable sensory attributes and acceptability with conventional dried noodles. Moreover, the sensory attributes including firmness, springiness, cohesiveness decreased, but stickiness increased with the increases of rice bran proportion in the salted noodles. These results inferred that incorporation of lower proportion of rice bran and lower power microwave-assisted dried noodles processing could produce faster cooking time and more acceptable quality of cooked noodles as compared to conventional dried noodles.Keywords: white salted noodles, microwave-assisted air drying processing, cooking yield, appearance, texture profiles, scanning electrical microscopy, sensory evaluation
Procedia PDF Downloads 4941494 Programmable Microfluidic Device Based on Stimuli Responsive Hydrogels
Authors: Martin Elstner
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Processing of information by means of handling chemicals is a ubiquitous phenomenon in nature. Technical implementations of chemical information processing lack of low integration densities compared to electronic devices. Stimuli responsive hydrogels are promising candidates for materials with information processing capabilities. These hydrogels are sensitive toward chemical stimuli like metal ions or amino acids. The binding of an analyte molecule induces conformational changes inside the polymer network and subsequently the water content and volume of the hydrogel varies. This volume change can control material flows, and concurrently information flows, in microfluidic devices. The combination of this technology with powerful chemical logic gates yields in a platform for highly integrated chemical circuits. The manufacturing process of such devices is very challenging and rapid prototyping is a key technology used in the study. 3D printing allows generating three-dimensional defined structures of high complexity in a single and fast process step. This thermoplastic master is molded into PDMS and the master is removed by dissolution in an organic solvent. A variety of hydrogel materials is prepared by dispenser printing of pre-polymer solutions. By a variation of functional groups or cross-linking units, the functionality of the hole circuit can be programmed. Finally, applications in the field of bio-molecular analytics were demonstrated with an autonomously operating microfluidic chip.Keywords: bioanalytics, hydrogels, information processing, microvalve
Procedia PDF Downloads 3091493 Experimental Investigation on the Anchor Behavior of Planar Clamping Anchor for Carbon Fiber-Reinforced Polymer Plate
Authors: Yongyu Duo, Xiaogang Liu, Qingrui Yue
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The anchor plays a critical role in the utilization of the tensile strength of carbon fiber-reinforced polymer (CFRP) plate when it is applied for the prestressed retrofitted and cable structures. In this paper, the anchor behavior of planar clamping anchor (PCA) under different interface treatment forms and normal pressures was investigated by the uniaxial static tensile test. Two interface treatment forms were adopted, including pure friction and the coupling action of friction and bonding. The results indicated that the load-bearing capacity of PCA could be obviously improved by the coupling action of friction and bonding compared with the action of pure friction. Under the normal pressure of 11 MPa, 22 MPa, and 33 MPa, the load-bearing capacity of PCA was enhanced by 164.61%, 68.40%, and 52.78%, respectively, and the tensile strength of the CFRP plate was fully exploited when the normal pressure reached 44 MPa. In addition, the experimental coefficient of static friction between the galling CFRP plate and a sandblasted steel plate was in the range of 0.28-0.30, corresponding to various normal pressure. Moreover, the failure mode was determined by the interface treatment form and normal pressure. The research in this paper has important guiding significance to optimize the design of the mechanical clamping anchor, contributing to promoting the application of CFRP plate in reinforcement and cable structure.Keywords: PCA, CFRP plate, interface treatment form, normal pressure, friction, coupling action
Procedia PDF Downloads 811492 Adaptation and Habituation to new Complete Dentures
Authors: Mohamed Khaled Ahmed Azzam
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Complete dentures, a non biological appliance, were and are still used to replace missing teeth and surrounding structures. Its main objectives are esthetics, speech, function and psychological state improvement. Dentists must realize that, just as dentate patients vary in their dental treatment complexity; edentulous patients also vary in the difficulty of their treatment plan. There are two main problems facing the removable Prosthodontist which harden his/her task how to please his patient with their new dentures being: Denture construction which however its fabrication is at the highest standards still is an unpleasant experience to all patients in the beginning and improves by time. This varies from one to several years according to the patient’s attitude, age, gender, socio-economical level and culture. The second problem of edentulous patients is both physical and psychological. Good interview, communication and note how patients present themselves for the concerns of their appearance, overall attitude and expectations concerning treatment is very important physically. On the psychological aspect patients have great difficulty to cope with new dentures to the extent of not using them at all. Hence their mind preparation should be commenced from day one by more than one method. This had a great impact on the acceptance which led to habituation to their dentures and patients were appreciative and pleased. In conclusion to successfully treat edentulous patients a great deal of information is required to complete a proper diagnosis, including patient mental attitude, past and present medical and dental conditions, and extra and intra-oral examinations. In addition to the clinical experience and skill of the whole dental team.Keywords: complete dentures, edentulous patients, management of denture, psychological mind preparation
Procedia PDF Downloads 2521491 Restoration Process of Kastamonu - Tufekciler Village Houses for Potential Eco-Tourism Purposes
Authors: Turkan Sultan Yasar Ismail, Mehmet Cetin, M. Danial Ismail, Hakan Sevik
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Nowadays, there is a need for the real world to be translated to the virtual environment by three-dimensional visualisation for restoration and promotional modelling of historic sites in protected areas. Visualisation models have also become the very important basis for the creation of three-dimensional Geographic Information System. The protection of historical and cultural heritage and documenting in Turkey as well as all over the world is an important issue. This heritage is a bridge between the past and the future of humanity. Many historical and cultural heritages suffer neglect and for reasons arising from natural causes. This is to determine the current status of the work and documenting information from the selected buildings. This process is important for their conservation and renovation work that might be done in the future. Kastamonu city is one of the historical cities in Turkey with a number of heritage buildings. However, Tufekciler Village is not visited and famous even though it includes several historical buildings and peaceful landscape. Digital terrestrial photogrammetry is one of the most important methods used in the documentation of cultural and historical heritage. Firstly, measurements were made primarily around creating polygon mesh and 3D model drawings of the structures to be modelled on images with the move to digital media such as picture size and by subsequent visualisation process. Secondly, a restoration project is offered to the village with the concept of eco-tourism with all scales such as, interior space to landscape design.Keywords: eco-tourism, restoration, sustainability, cultural village
Procedia PDF Downloads 3521490 Induced Chemistry for Dissociative Electron Attachment to Focused Electron Beam Induced Deposition Precursors Based on Ti, Si and Fe Metal Elements
Authors: Maria Pintea, Nigel Mason
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Induced chemistry is one of the newest pathways in the nanotechnology field with applications in the focused electron beam induced processes for deposition of nm scale structures. Si(OPr)₄ and Ti(OEt)₄ are two of the precursors that have not been so extensively researched, though highly sought for semiconductor and medical applications fields, the two compounds make good candidates for FEBIP and are the subject of velocity slice map imaging analysis for deposition purposes, offering information on kinetic energies, fragmentation channels, and angular distributions. The velocity slice map imaging technique is a method used for the characterization of molecular dynamics of the molecule and the fragmentation channels as a result of induced chemistry. To support the gas-phase analysis, Meso-Bio-Nano simulations of irradiation dynamics studies are employed with final results on Fe(CO)₅ deposited on various substrates. The software is capable of running large scale simulations for complex biomolecular, nano- and mesoscopic systems with applications to thermos-mechanical DNA damage, complex materials, gases, nanoparticles for cancer research and deposition applications for nanotechnology, using a large library of classical potentials, many-body force fields, molecular force fields involved in the classical molecular dynamics.Keywords: focused electron beam induced deposition, FEBID, induced chemistry, molecular dynamics, velocity map slice imaging
Procedia PDF Downloads 1091489 Mainstreaming Climate Change Adaptation into National and Sectoral Policies in Nepal
Authors: Bishwa Nath Oli
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Nepal is highly impacted by climate change and adaptation has been a major focus. This paper investigates the gaps and coherence in national policies across water, forestry, local development and agriculture sectors, identifies their links to climate change adaptation and national development plans and analyzes the effectiveness of climate change policy on adaptation. The study was based on a content analysis of relevant policy documents on the level of attention given to adaptation and key informant interviews. Findings show that sectoral policies have differing degrees of cross thematic coherence, often with mismatched priorities and differing the paths towards achieving climate change goal. They are somewhat coherent in addressing immediate disaster management issues rather than in climate adaptation. In some cases, they are too broad and complicated and the implementation suffers from barriers and limits due to lack of capacity, investment, research and knowledge needed for evidence-based policy process. They do not adequately provide operational guidance in supporting communities in adapting to climate change. The study recommends to a) embrace longer-term cross-sectoral planning within government structures to foster greater policy coherence and integrated adaptation planning, b) increase awareness and flow of information on the potential role of communities in climate change, c) review the existing development sectors from the climate change perspectives, and d) formulate a comprehensive climate change legislation based on the need to implement the new Constitution.Keywords: agriculture, climate change adaptation, forestry, policies
Procedia PDF Downloads 2221488 Kinetic Study of C₃N₄/CuWO₄: Photocatalyst towards Solar Light Inactivation of Mixed Populated Bacteria
Authors: Rimzhim Gupta, Bhanupriya Boruah, Jayant M. Modak, Giridhar Madras
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Microbial contamination is one of the major concerns in the field of water treatment. AOP (advanced oxidation processes) is well-established method to resolve the issue of removal of contaminants in water. A Z-scheme composite g-C₃N₄/CuWO₄ was synthesized by sol-gel method for the photocatalytic inactivation of a mixed population of Gram-positive bacteria (S. aureus) and Gram-negative bacteria (E. coli). The photoinactivation was observed for different types of bacteria in the same medium together and individually in the absence of the nutrients. The lattice structures and phase purities were determined by X-ray diffraction. For morphological and topographical features, scanning electron microscopy and transmission electron microscopy analyses were carried out. The band edges of the semiconductor (valence band and conduction band) were determined by ultraviolet photoelectron microscopy. The lifetime of the charge carriers and band gap of the semiconductors were determined by time resolved florescence spectroscopy and diffused reflectance spectroscopy, respectively. The effect of weight ratio of C₃N₄ and CuWO₄ was observed by performing photocatalytic experiments. To investigate the exact mechanism and major responsible radicals for photocatalysis, scavenger studies were performed. The rate constants and order of the inactivation reactions were obtained by power law kinetics. For E. coli and S. aureus, the order of reaction and rate constants are 1.15, 0.9 and 1.39 ± 0.03 (CFU/mL)⁻⁰.¹⁵ h⁻¹, 47.95 ± 1.2 (CFU/mL)⁰.¹ h⁻¹, respectively.Keywords: z-scheme, E. coli, S. aureus, sol-gel
Procedia PDF Downloads 1481487 Synthetic Access to Complex Metal Carbonates and Hydroxycarbonates via Sol-Gel Chemistry
Authors: Schirin Hanf, Carlos Lizandara-Pueyo, Timmo P. Emmert, Ivana Jevtovikj, Roger Gläser, Stephan A. Schunk
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Metal alkoxides are very versatile precursors for a broad array of complex functional materials. However, metal alkoxides, especially transition metal alkoxides, tend to form oligomeric structures due to the very strong M–O–M binding motif. This fact hinders their facile application in sol-gel-processes and complicates access to complex carbonate or oxidic compounds after hydrolysis of the precursors. Therefore, the development of a synthetic alternative with the aim to grant access to carbonates and hydroxycarbonates from simple metal alkoxide precursors via hydrolysis is key to this project. Our approach involves the reaction of metal alkoxides with unsaturated isoelectronic molecules, such as carbon dioxide. Subsequently, a stoichiometric insertion of the CO₂ into the alkoxide M–O bond takes place and leads to the formation of soluble metal alkyl carbonates. This strategy is a very elegant approach to solubilize metal alkoxide precursors to make them accessible for sol-gel chemistry. After hydrolysis of the metal alkyl carbonates, crystalline metal carbonates, and hydroxycarbonates can be obtained, which were then utilized for the synthesis of Cu/Zn based bulk catalysts for methanol synthesis. Using these catalysts, a comparable catalytic activity to commercially available MeOH catalysts could be reached. Based on these results, a complement for traditional precipitation techniques, which are usually utilized for the synthesis of bulk methanol catalysts, have been found based on an alternative solubilization strategy.Keywords: metal alkoxides, metal carbonates, metal hydroxycarbonates, CO₂ insertion, solubilization
Procedia PDF Downloads 1871486 Aspects of the Promotional Language of Tourism in Social Media. A Case Study of Romanian Accommodation Industry
Authors: Sanda-Maria Ardeleanu, Ana Crăciunescu
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This paper is sustained by our previous research on discursive strategies, whichdemonstrated that tourismhas developed and employed apromotional languageper se. We have studied this concept within the framework of audio-visual advertising by analyzing its discursive structures at the level of three main strategies (textual, visual, and both textual and visual) and confirmed the applicability of the promotional language per se within the field. Tourism, at large, represents a largely potential interdisplinary field, which allowed us to use qualitative methods of research such as Discourse Analysis (DA). Due to further research which showed that in the third phase of qualitative research methodologies, scholars in tourism recognized semiotics and DA as potential paths to follow, but which were insufficiently explored at the time, we soon realized that the natural next step to take is to bring together common qualitative methodologies for both fields, such as the method of observation, the triangulation, Discourse Analysis, etc. Therefore and in the light of fast transformations of the medium that intermediates the message, in this paper, we are going to focus on the manifestations of the promotional language in social media texts, which advertise for the urban industry of accommodation in Romania. We shall constitute a corpus of study as the basis for our research methodology and, through the empirical method of observation and DA, we propose to recognize or discover new patterns developed at textual (mainly) and visual level or the mix of the two, known as strategies of the promotional language of tourism.Keywords: discourse analysis, promotional language of tourism, social media, urban accommodation industry, tourism
Procedia PDF Downloads 1661485 Silica Sulfuric Acid as an Efficient Catalyst One-Pot Three-Component Aza-Friedel-Crafts Reactions of 2-(thiophen-2-yl)-1H-Indole, Aldehydes, and N-Substituted Anilines
Authors: Nagwa Mourad Abdelazeem, Marwa El-hussieny
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Multicomponent reactions (MCRs), one-pot reactions form products from more than two different starting compounds. (MCRs) are ideal reaction systems leading to high structural diversity and molecular complexity through a single transformation. (MCRs) have a lot of advantage such as higher yield, less waste generation, use of readily available starting materials and high atom. (MCRs) provide a rapid process for efficient synthesis of key structures in discovery of drug on the other hand silica sulfuric acid (SSA) has been used as an efficient heterogeneous catalyst for many organic transformations. (SSA) is low cost, ease of preparation, catalyst recycling, and ease of handling, so in this article we used 2-(thiophen-2-yl)-1H-indole, N-substituted anilines and aldehyde in the presence of silica sulfuric acid (SSA) as a catalyst in water as solvent at room temperature to prepare 3,3'-(phenylmethylene)bis(2-(thiophen-2-yl)-1H-indole) and N-methyl-4-(phenyl(2-(thiophen-2-yl)-1H-indol-3-yl)methyl)aniline derivatives Via one-pot reaction. Compound 2-(thiophen-2-yl)-1H-indole belongs to the ubiquitous class of indoles which enjoy broad synthetic, biological and industrial applications ]. Cancer is considered the first or second most common reason of death all through the world. So the synthesized compounds will be tested as anticancer. We expected the synthesized compounds will give good results comparison to the reference drug.Keywords: aldehydes, aza-friedel-crafts reaction, indole, multicomponent reaction
Procedia PDF Downloads 971484 Structural, Electrochemical and Electrocatalysis Studies of a New 2D Metal-Organic Coordination Polymer of Ni (II) Constructed by Naphthalene-1,4-Dicarboxylic Acid; Oxidation and Determination of Fructose
Authors: Zohreh Derikvand
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One new 2D metal-organic coordination polymer of Ni(II) namely [Ni2(ndc)2(DMSO)4(H2O)]n, where ndc = naphthalene-1,4-dicarboxylic acid and DMSO= dimethyl sulfoxide has been synthesized and characterized by elemental analysis, spectral (IR, UV-Vis), thermal (TG/DTG) analysis and single crystal X-ray diffraction. Compound 1 possesses a 2D layer structure constructed from dinuclear nickel(II) building blocks in which two crystallographically independent Ni2+ ions are bridged by ndc2– ligands and water molecule. The ndc2– ligands adopt μ3 bridging modes, linking the metal centers into a two-dimensional coordination framework. The two independent NiII cations are surrounded by dimethyl sulfoxide and naphthalene-1,4-dicarboxylate molecules in distorted octahedron geometry. In the crystal structures of 1 there are non-classical hydrogen bonding arrangements and C-H–π stacking interactions. Electrochemical behavior of [Ni2(ndc)2(DMSO)4(H2O)]n, (Ni-NDA) on the surface of carbon nanotube (CNTs) glassy carbon electrode (GCE) was described. The surface structure and composition of the sensor were characterized by scanning electron microscopy (SEM). Oxidation of fructose on the surface of modified electrode was investigated with cyclic voltammetry and electrochemical impedance spectroscopy (EIS) and the results showed that the Ni-NDA/CNTs film displays excellent electrochemical catalytic activities towards fructose oxidation.Keywords: naphthalene-1, 4-dicarboxylic acid, crystal structure, coordination polymer, electrocatalysis, impedance spectroscopy
Procedia PDF Downloads 332