Search results for: wall effect
14809 Influence of Thermal Ageing on Microstructural Features and Mechanical Properties of Reduced Activation Ferritic/Martensitic Grades
Authors: Athina Puype, Lorenzo Malerba, Nico De Wispelaere, Roumen Petrov, Jilt Sietsma
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Reduced Activation Ferritic/Martensitic (FM) steels like EUROFER are of interest for first wall application in the future demonstration (DEMO) fusion reactor. Depending on the final design codes for the DEMO reactor, the first wall material will have to function in low-temperature mode or high-temperature mode, i.e. around 250-300°C of above 550°C respectively. However, the use of RAFM steels is limited up to a temperature of about 550°C. For the low-temperature application, the material suffers from irradiation embrittlement, due to a shift of ductile-to-brittle transition temperature (DBTT) towards higher temperatures upon irradiation. The high-temperature response of the material is equally insufficient for long-term use in fusion reactors, due to the instability of the matrix phase and coarsening of the precipitates at prolonged high-temperature exposure. The objective of this study is to investigate the influence of thermal ageing for 1000 hrs and 4000 hrs on microstructural features and mechanical properties of lab-cast EUROFER. Additionally, the ageing behavior of the lab-cast EUROFER is compared with the ageing behavior of standard EUROFER97-2 and T91. The microstructural features were investigated with light optical microscopy (LOM), electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM). Additionally, hardness measurements, tensile tests at elevated temperatures and Charpy V-notch impact testing of KLST-type MCVN specimens were performed to study the microstructural features and mechanical properties of four different F/M grades, i.e. T91, EUROFER97-2 and two lab-casted EUROFER grades. After ageing for 1000 hrs, the microstructures exhibit similar martensitic block sizes independent on the grain size before ageing. With respect to the initial coarser microstructures, the aged microstructures displayed a dislocation structure which is partially fragmented by polygonization. On the other hand, the initial finer microstructures tend to be more stable up to 1000hrs resulting in similar grain sizes for the four different steels. Increasing the ageing time to 4000 hrs, resulted in an increase of lath thickness and coarsening of M23C6 precipitates leading to a deterioration of tensile properties.Keywords: ageing experiments, EUROFER, ferritic/martensitic steels, mechanical properties, microstructure, T91
Procedia PDF Downloads 26114808 A Failure Investigations of High-Temperature Hydrogen Attack at Plat Forming Unit Furnace Elbow
Authors: Altoumi Alndalusi
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High-temperature hydrogen attack (HTHA) failure is the common phenomena at elevated temperature in hydrogen environment in oil and gas field. The failure occurred once after four years at the internal surface of Platforming elbow. Both visual and microscopic examinations revealed that the failure was initiated due to blistering forming followed by large cracking at the inner surface. Crack morphology showed that the crack depth was about 50% of material wall thickness and its behavior generally was intergranular. This study concluded that the main reason led to failure due to incorrect material selection comparing to the platforming conditions.Keywords: decarburization, failure, heat affected zone, morphology, partial pressure, plate form
Procedia PDF Downloads 15614807 The Structural Pattern: An Event-Related Potential Study on Tang Poetry
Authors: ShuHui Yang, ChingChing Lu
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Measuring event-related potentials (ERPs) has been fundamental to our understanding of how people process language. One specific ERP component, a P600, has been hypothesized to be associated with syntactic reanalysis processes. We, however, propose that the P600 is not restricted to reanalysis processes, but is the index of the structural pattern processing. To investigate the structural pattern processing, we utilized the effects of stimulus degradation in structural priming. To put it another way, there was no P600 effect if the structure of the prime was the same with the structure of the target. Otherwise, there would be a P600 effect if the structure were different between the prime and the target. In the experiment, twenty-two participants were presented with four sentences of Tang poetry. All of the first two sentences, being prime, were conducted with SVO+VP. The last two sentences, being the target, were divided into three types. Type one of the targets was SVO+VP. Type two of the targets was SVO+VPVP. Type three of the targets was VP+VP. The result showed that both of the targets, SVO+VPVP and VP+VP, elicited positive-going brainwave, a P600 effect, at 600~900ms time window. Furthermore, the P600 component was lager for the target’ VP+VP’ than the target’ SVO+VPVP’. That meant the more dissimilar the structure was, the lager the P600 effect we got. These results indicate that P600 was the index of the structure processing, and it would affect the P600 effect intensity with the degrees of structural heterogeneity.Keywords: ERPs, P600, structural pattern, structural priming, Tang poetry
Procedia PDF Downloads 14014806 A Simulation Model and Parametric Study of Triple-Effect Desalination Plant
Authors: Maha BenHamad, Ali Snoussi, Ammar Ben Brahim
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A steady-state analysis of triple-effect thermal vapor compressor desalination unit was performed. A mathematical model based on mass, salinity and energy balances is developed. The purpose of this paper is to develop a connection between process simulator and process optimizer in order to study the influence of several operating variables on the performance and the produced water cost of the unit. A MATLAB program is used to solve the model equations, and Aspen HYSYS is used to model the plant. The model validity is examined against a commercial plant and showed a good agreement between industrial data and simulations results. Results show that the pressures of the last effect and the compressed vapor have an important influence on the produced cost, and the increase of the difference temperature in the condenser decreases the specific heat area about 22%.Keywords: steady-state, triple effect, thermal vapor compressor, Matlab, Aspen Hysys
Procedia PDF Downloads 17214805 Behavior of GRS Abutment Facing under Variable Cycles of Lateral Excitation through Physical Model Tests
Authors: Ashutosh Verma, Satyendra Mittal
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Numerous geosynthetic reinforced soil (GRS) abutment failures over the years have been attributed to the loss of strength at the facing-reinforcement interface due to seasonal thermal expansion/contraction of the bridge deck. This causes excessive settlement below the bridge seat, causing bridge bumps along the approach road which reduces the design life of any abutment. Before designers while choosing the type of facing, a broad range of facing configurations are undoubtedly available. Generally speaking, these configurations can be divided into three groups: modular (panels/block), continuous, and full height rigid (FHR). The purpose of the current study is to use 1g physical model tests under serviceable cyclic lateral displacements to experimentally investigate the behaviour of these three facing classifications. To simulate field behaviour, a field instrumented GRS abutment prototype was modeled into a N scaled down 1g physical model (N = 5) with adjustable facing arrangements to represent these three facing classifications. For cyclic lateral displacement (d/H) of top facing at loading rate of 1mm/min, the peak earth pressure coefficient (K) on the facing and vertical settlement of the footing (s/B) at 25, 50, 75 and 100 cycles have been measured. For a constant footing offset of x/H = 0.1, three forms of cyclic displacements have been performed to simulate active condition (CA), passive condition (CP), and active-passive condition (CAP). The findings showed that when reinforcements are integrated into the wall along with presence of gravel gabions i.e. FHR design, a rather substantial earth pressure occurs over the facing. Despite this, the FHR facing's continuous nature works in conjunction with the reinforcements' membrane resilience to reduce footing settlement. On the other hand, the pressure over the wall is released upon lateral excitation by the relative displacement between the panels in modular facing reducing the connection strength at the interface and leading to greater settlements below footing. On the contrary, continuous facing do not exhibit relative displacement along the depth of facing rather fails through rotation about the base, which extends the zone of active failure in the backfill leading to large depressions in the backfill region around the bridge seat. Conservatively, FHR facing shows relatively stable responses under lateral cyclic excitations as compared to modular or continuous type of abutment facing.Keywords: GRS abutments, 1g physical model, full height rigid, cyclic lateral displacement
Procedia PDF Downloads 8314804 Supplementation of Citrulline with Lactic Acid Bacteria Protects Foodborne Pathogens Adhesion and Improves the Cell Integrity on the Intestinal Epithelial Cell
Authors: Sze Wing Ho, Nagendra P. Shah
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Lactic acid bacteria (LAB) have shown the beneficial effects on human gastrointestinal tract, such as protects diarrhea induced by lactose intolerance or enteric pathogens. Citrulline is a non-protein amino acid and also the precursors of arginine and nitric oxide, it has shown to enhance intestinal barrier function. Citrulline has shown to improve the growth of some strains of LAB, it is important for LAB to have a sufficient cell concentration to contribute the effects. Therefore, the aims of this study were to investigate the effect of combining citrulline with LAB on the anti-adhesion effect against pathogens and the effect on the cell integrity. The effect of citrulline on selected LAB was determined by incubating in 0%, 0.1% or 0.2% citrulline enriched MRS broth for 18 h. The adhesion ability of LAB and the anti-adhesion effect of LAB and citrulline against pathogens were performed on IPEC-J2 cell line. Transepithelial electrical resistance (TEER) assay was used to measure the tight junction (TJ) integrity. TJ proteins (claudin-1, occludin and zonula occluden-1 (ZO-1)) were determined by western blot analysis. It found that the growth of Lactobacillus helveticus ASCC 511 was significantly stimulated by 0.2% citrulline compared with control during 18 h fermentation. The adhesion of L. helveticus ASCC 511 and Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) ASCC 756 was increased when supplemented with citrulline. Citrulline has shown significant inhibitory effect on the adhesion of Escherichia coli PELI0480 (O157:H7), Shigella sonnei ATCC 25931, Staphyloccocus aureus CMCC26003 and Cronobacter sakazakii ATCC 29544. The anti-adhesion effect of L. helveticus ASCC 511, L. bulgaricus ASCC 756 and Lactobacillus paracasei ASCC 276 against Cronobacter sakazakii ATCC 29544 was significantly enhanced with citrulline supplementation. Treatments with citrulline and LAB were able to maintain the TEER of IPEC-J2 cell and shown the positive effect on the TJ proteins. In conclusion, citrulline had stimulating effect on some strains of LAB and determined to improve the adhesion of LAB on intestinal epithelial cell, to enhance the inhibitory effect on enteric pathogens adhesion as well as had beneficial effects on maintaining cell integrity. It implied LAB supplemented with citrulline might have advantageous effects on gastrointestinal tracts.Keywords: citrulline, lactic acid bacteria, amino acid, anti-adhesion effect, cell integrity
Procedia PDF Downloads 23814803 Synthesis of an Organic-Inorganic Salt of (C2H5NO2) 2H4SiW12O40 and Investigation of Its Anti-Viral Effect on the Tobacco Mosaic Virus (TMV)
Authors: Mahboobeh Mohadeszadeh, Majid Saghi
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Polyoxometalates (POMs) are important inorganic compounds that have been considered specifically in recent years due to abundant attributes and applications. Those POMs that have one central tetrahedral atom called keggin. The binding Amino-acid groups to keggin structure give the antivirus effect to these compounds. A new organic-inorganic hybrid structure, with formula (Gly)2H4SiW12O40 was synthesized. Investigation on Anti-viral effect of this compound showed the (Gly)2H4SiW12O40 prevents infection of Tobacco Mosaic Virus (TMV) on the Nicotianatabacum plants.Keywords: Polyoxometalate, Keggin, Organic-inorganic salt, TMV
Procedia PDF Downloads 28814802 Synthesis of an Organic- Inorganic Salt of (C2H5NO2)2H4SiW12O40 and Investigation of Its Anti-Viral Effect on the Tobacco Mosaic Virus (TMV)
Authors: Mahboobeh Mohadeszadeh, Majid Saghi
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Polyoxometalates (POMs) are important inorganic compounds that have been considered specifically in recent years due to abundant attributes and applications. Those POMs that have one central tetrahedral atom called keggin. The binding Amino-acid groups to keggin structure give the antivirus effect to these compounds. A new organic-inorganic hybrid structure, with formula (Gly)2H4SiW12O40 was synthesized. Investigation on Anti-viral effect of this compound showed the (Gly)2H4SiW12O40 prevents infection of Tobacco Mosaic Virus (TMV) on the Nicotianatabacum plants.Keywords: polyoxometalate, keggin, organic-inorganic salt, TMV
Procedia PDF Downloads 42114801 Effects of Molybdenum on Phosphorus Concentration in Rice (Oryza sativa L.)
Authors: Hamed Zakikhani, Mohd Khanif Yusop, Amin Soltangheisi
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A hydroponic trial was carried out to investigate the effect of molybdenum (Mo) on uptake of phosphorus (P) in different rice cultivars. The experiment was conducted using a randomized complete-block design, with a split-plot arrangement of treatments and three replications. Four rates of Mo (0, 0.01, 0.1 and 1 mg L−1) and five cultivars (MR219, HASHEMI, MR232, FAJRE and MR253) provided the main and sub-plots, respectively. Interaction of molybdenum×variety was significant on shoot phosphorus uptake (p≤0.01). Highest and lowest shoot phosphorus uptake were seen in Mo3V3 (0.6% plant-1) and Mo0V3 (0.14% plant-1) treatments, respectively. Molybdenum did not have a significant effect on root phosphorus content. According to results, application of molybdenum has a synergistic effect on uptake of phosphorus by rice plants.Keywords: molybdenum, phosphorus, uptake, rice,
Procedia PDF Downloads 43514800 Hydromagnetic Linear Instability Analysis of Giesekus Fluids in Taylor-Couette Flow
Authors: K. Godazandeh, K. Sadeghy
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In the present study, the effect of magnetic field on the hydrodynamic instability of Taylor-Couette flow between two concentric rotating cylinders has been numerically investigated. At the beginning the basic flow has been solved using continuity, Cauchy equations (with regards to Lorentz force) and the constitutive equations of a viscoelastic model called "Giesekus" model. Small perturbations, considered to be normal mode, have been superimposed to the basic flow and the unsteady perturbation equations have been derived consequently. Neglecting non-linear terms, the general eigenvalue problem obtained has been solved using pseudo spectral method (combination of Chebyshev polynomials). The objective of the calculations is to study the effect of magnetic fields on the onset of first mode of instability (axisymmetric mode) for different dimensionless parameters of the flow. The results show that the stability picture is highly influenced by the magnetic field. When magnetic field increases, it first has a destabilization effect which changes to stabilization effect due to more increase of magnetic fields. Therefor there is a critical magnetic number (Hartmann number) for instability of Taylor-Couette flow. Also, the effect of magnetic field is more dominant in large gaps. Also based on the results obtained, magnetic field shows a more considerable effect on the stability at higher Weissenberg numbers (at higher elasticity), while the "mobility factor" changes show no dominant role on the intense of suction and injection effect on the flow's instability.Keywords: magnetic field, Taylor-Couette flow, Giesekus model, pseudo spectral method, Chebyshev polynomials, Hartmann number, Weissenberg number, mobility factor
Procedia PDF Downloads 39014799 Ramadan and Ethical Integrity in the United Arab Emirates
Authors: Gabriel Andrade
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Background: Ramadan is a time of intense religious salience in the Islamic world. Apart from ritual engagement, it is also a time for reflection on devotion and shared humanity. This prompts the issue if Ramadan has an effect on moral integrity and decision-making. Methods: The present study seeks to answer that question. A group of Muslim students in the United Arab Emirates (UAE) were assessed on moral integrity both during and after Ramadan. Results: Results came out showing that Ramadan has no significant effect on participants’ moral integrity. Conclusion: It is concluded that Ramadan has no effect on participants’ moral behavior, and this is potentially explained by the UAE’s increased secularization in recent decades.Keywords: Ramadan, United Arab Emirates, moral integrity, secularization, trolley dilemmas
Procedia PDF Downloads 4214798 A Meta-Analysis of Handwriting and Visual-Motor Integration (VMI): The Moderating Effect of Handwriting Dimensions
Authors: Hong Lu, Xin Chen, Zhengcheng Fan
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Prior research has claimed a close association between handwriting and mathematics attainment with the help of spatial cognition. However, the exact mechanism behind this relationship remains un-investigated. Focusing on visual-motor integration (VMI), one critical spatial skill, this meta-analysis aims to estimate the size of the handwriting- visual-motor integration relationship and examine the moderating effect of handwriting dimensions on the link. With a random effect model, a medium relation (r=.26, 95%CI [.22, .30]) between handwriting and VMI was summarized in 38 studies with 55 unique samples and 141 effect sizes. Findings suggested handwriting dimensions significantly moderated the handwriting- VMI relationship, with handwriting legibility showing a substantial correlation with VMI, but neither handwriting speed nor pressure. Identifying the essential relationship between handwriting legibility and VMI, this study adds to the literature about the key cognitive processing needs underlying handwriting, and spatial cognition thus highlights the cognitive mechanism regarding handwriting, spatial cognition, and mathematics performances.Keywords: handwriting, visual-motor integration, legibility, meta-analysis
Procedia PDF Downloads 10914797 Allelopathic Effect of Foliar Extracts of Leucaena leucocephala on Germination and Growth Behavior of Zea mays L.
Authors: Guru Prasad Satsangi, Shiv Shankar Gautam
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Allelopathy is a potential area of research for sustainable agriculture. It is environmentally safe, can conserve the available resources, and also may mitigate the problems raised by synthetic chemicals. The allelo-chemicals are secondary metabolites produced by plants, which are the byproducts of the primary metabolic process. These allelo-chemicals may be stimulatory, inhibitory, or may have no effect on the growth of the other plants. It has been observed in the present study that foliar extracts of Leucaena leucocephala showed an inhibitory effect on the germination of the test crop maize. The results revealed that at different concentrations of Leucaena leucocephala foliar extract, caused a significant inhibition in germination and growth behavior of Zea mays L. seedlings. Minimum germination and growth occurred in 100 % concentration, and an increase in extract concentrations result in a decrease in the germination. Bioassay also depicted that this inhibitory effect was proportional to the concentration of the extract as the higher concentration having a lesser stimulatory effect or vice versa. The phytochemical analysis of the secondary metabolites from foliar extracts of Leucaena leucocephala L. showed the presence of tannins, saponins, phenols, alkaloids, and flavanoids. Among various extracts, the presence of methanol extract was found in a significant amount of phytochemicals, followed by the aqueous and ethanol extracts. Leaves showed a significantly higher amount of the allelochemicals.Keywords: allelopathic effect, germination /growth behavior , foliar extracts, Leucaena leucceophala , Zea mays L.
Procedia PDF Downloads 20014796 Synthesis of an Organic-Inorganic Salt of 12-Silicotungstate, (C2H5NO2)2H4SiW12O40 and Investigation of Its Anti-Viral Effect on the Tobacco Mosaic Virus
Authors: Mahboobeh Mohadeszadeh, Majid Saghi
Abstract:
Polyoxometalates (POMs) are important inorganic compounds that have been considered specifically in recent years due to abundant attributes and applications. Those POMs that have one central tetrahedral atom called keggin. The binding Amino-acid groups to keggin structure give the antivirus effect to these compounds. A new organic-inorganic hybrid structure, with formula (Gly)2H4SiW12O40, was synthesized. Investigation on the anti-viral effect of this compound showed the (Gly)2H4SiW12O40 prevents infection of Tobacco Mosaic Virus (TMV) on the Nicotianatabacum plants.Keywords: polyoxometalate, keggin, organic-inorganic salt, TMV
Procedia PDF Downloads 29114795 Effect of Vanadium Addition to Aluminum Grain Refined by Ti or Ti + B on Its Microstructure, Mechanical Behavior, Fatigue Strength and Life
Authors: Adnan I. O. Zaid
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As aluminum solidifies in columnar structure with large grain size which reduces its surface quality and mechanical strength; therefore it is normally grain refined either by titanium or titanium + boron (Ti or Ti + B). In this paper, the effect of addition of either Ti or Ti + B to commercially pure aluminum on its grain size, Vickers hardness, mechanical strength and fatigue strength and life is presented and discussed. Similarly, the effect of vanadium addition to Al grain refined by Ti or Ti+ B is presented and discussed. Two binary master alloys Al-Ti and Al-Vi were laboratory prepared from which five different micro-alloys in addition to the commercially pure aluminum namely Al-Ti, Al-Ti-B, Al-V, Al-Ti-V and Al-Ti-B-V were prepared for the investigation. Finally, the effect of their addition on the fatigue cracks initiation and propagation, using scanning electron microscope, SEM, is also presented and discussed. Photomirographs and photoscans are included in the paper.Keywords: aluminum, fatigue, grain refinement, titanium, titanium+boron, vanadium
Procedia PDF Downloads 48614794 Fama French Four Factor Model: A Study of Nifty Fifty Companies
Authors: Deeksha Arora
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The study aims to explore the applicability of the widely used asset pricing models, namely, Capital Asset Pricing Model (CAPM) and the Fama-French Four Factor Model in the Indian equity market. The study will be based on the companies that form part of the Nifty Fifty Index for a period of five years: 2011 to 2016. The asset pricing model is examined by forming portfolios on the basis of three variables – market capitalization (size effect), book-to-market equity ratio (value effect) and profitability. The study provides a basis to test the presence of the Fama-French Four factor model in Indian stock market. This study may provide a basis for future research in the generalized asset pricing model comprising of multiple risk factors.Keywords: book to market equity, Fama French four factor model, market capitalization, profitability, size effect, value effect
Procedia PDF Downloads 26314793 Numerical Studies on Bypass Thrust Augmentation Using Convective Heat Transfer in Turbofan Engine
Authors: R. Adwaith, J. Gopinath, Vasantha Kohila B., R. Chandru, Arul Prakash R.
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The turbofan engine is a type of air breathing engine that is widely used in aircraft propulsion produces thrust mainly from the mass-flow of air bypassing the engine core. The present research has developed an effective method numerically by increasing the thrust generated from the bypass air. This thrust increase is brought about by heating the walls of the bypass valve from the combustion chamber using convective heat transfer method. It is achieved computationally by the use external heat to enhance the velocity of bypass air of turbofan engines. The bypass valves are either heated externally using multicell tube resistor which convert electricity generated by dynamos into heat or heat is transferred from the combustion chamber. This increases the temperature of the flow in the valves and thereby increase the velocity of the flow that enters the nozzle of the engine. As a result, mass-flow of air passing the core engine for producing more thrust can be significantly reduced thereby saving considerable amount of Jet fuel. Numerical analysis has been carried out on a scaled down version of a typical turbofan bypass valve, where the valve wall temperature has been increased to 700 Kelvin. It is observed from the analysis that, the exit velocity contributing to thrust has significantly increased by 10 % due to the heating of by-pass valve. The degree of optimum increase in the temperature, and the corresponding effect in the increase of jet velocity is calculated to determine the operating temperature range for efficient increase in velocity. The technique used in the research increases the thrust by using heated by-pass air without extracting much work from the fuel and thus improve the efficiency of existing turbofan engines. Dimensional analysis has been carried to prove the accuracy of the results obtained numerically.Keywords: turbofan engine, bypass valve, multi-cell tube, convective heat transfer, thrust
Procedia PDF Downloads 35814792 Effect of the Applied Bias on Miniband Structures in Dimer Fibonacci Inas/Ga1-Xinxas Superlattices
Authors: Z. Aziz, S. Terkhi, Y. Sefir, R. Djelti, S. Bentata
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The effect of a uniform electric field across multibarrier systems (InAs/InxGa1-xAs) is exhaustively explored by a computational model using exact airy function formalism and the transfer-matrix technique. In the case of biased DFHBSL structure a strong reduction in transmission properties was observed and the width of the miniband structure linearly decreases with the increase of the applied bias. This is due to the confinement of the states in the miniband structure, which becomes increasingly important (Wannier-Stark Effect).Keywords: dimer fibonacci height barrier superlattices, singular extended state, exact airy function, transfer matrix formalism
Procedia PDF Downloads 30514791 Rotor Radial Vent Pumping in Large Synchronous Electrical Machines
Authors: Darren Camilleri, Robert Rolston
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Rotor radial vents make use of the pumping effect to increase airflow through the active material thus reduce hotspot temperatures. The effect of rotor radial pumping in synchronous machines has been studied previously. This paper presents the findings of previous studies and builds upon their theories using a parametric numerical approach to investigate the rotor radial pumping effect. The pressure head generated by the poles and radial vent flow-rate were identified as important factors in maximizing the benefits of the pumping effect. The use of Minitab and ANSYS Workbench to investigate the key performance characteristics of radial pumping through a Design of Experiments (DOE) was described. CFD results were compared with theoretical calculations. A correlation for each response variable was derived through a statistical analysis. Findings confirmed the strong dependence of radial vent length on vent pressure head, and radial vent cross-sectional area was proved to be significant in maximising radial vent flow rate.Keywords: CFD, cooling, electrical machines, regression analysis
Procedia PDF Downloads 31214790 In vitro Culture of Stem Node Segments of Maerua crassifolia
Authors: Abobaker Abrahem M. Saad, Asma Abudasalam
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The stem node segments were cultured on Murashige and Skoog (MS) medium. In the case of using MS+ Zeatin (1 mg/l), small shoot buds were formed directly in 70% of explants after 15 days, their length range between 0.1 to 0.3 cm after two weeks and reached 0.3 cm in length and three shoots in numbers after 4 weeks. When those small shoots were sub cultured on the same medium, they increased in length, number and reached 0.4 cm with 4 shoots, 0.4 cm with 5 shoots after six, eight and ten weeks respectively. In the case of using MS free hormones, MS+IAA (0.2mg/l) +BA (0.5mg/l), MS + kin(0.5mg/l), MS + kin (3mg/l) and MS +NAA (3mg/l) +BA (1mg/l), no sign of responses were noticed and only change in color in some cases. Different types of parenchyma cells and many layers of thick wall sclerenchyma cells were observed on MS+BA (1mg/l).Keywords: Maerua, stem node, shoots, buds, In vitro
Procedia PDF Downloads 31214789 Elasto-Plastic Behavior of Rock during Temperature Drop
Authors: N. Reppas, Y. L. Gui, B. Wetenhall, C. T. Davie, J. Ma
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A theoretical constitutive model describing the stress-strain behavior of rock subjected to different confining pressures is presented. A bounding surface plastic model with hardening effects is proposed which includes the effect of temperature drop. The bounding surface is based on a mapping rule and the temperature effect on rock is controlled by Poisson’s ratio. Validation of the results against available experimental data is also presented. The relation of deviatoric stress and axial strain is illustrated at different temperatures to analyze the effect of temperature decrease in terms of stiffness of the material.Keywords: bounding surface, cooling of rock, plasticity model, rock deformation, elasto-plastic behavior
Procedia PDF Downloads 12714788 Soil Arching Effect in Columnar Embankments: A Numerical Study
Authors: Riya Roy, Anjana Bhasi
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Column-supported embankments provide a practical and efficient solution for construction on soft soil due to the low cost and short construction times. In the recent years, geosynthetic have been used in combination with column systems to support embankments. The load transfer mechanism in these systems is a combination of soil arching effect, which occurs between columns and membrane effect of the geosynthetic. This paper aims at the study of soil arching effect on columnar embankments using finite element software, ABAQUS. An axisymmetric finite element model is generated and using this model, parametric studies are carried out. Thus the effects of various factors such as height of embankment fill, elastic modulus of pile and tensile stiffness of geosynthetic, on soil arching have been studied. The development of negative skin friction along the pile-soil interface have also been studied and the results obtained from this study are compared with the current design methods.Keywords: ABAQUS, geosynthetic, negative skin friction, soil arching
Procedia PDF Downloads 37914787 Mediating Effect of Hopefulness on the Effect of Underdog Narratives to Subjective Well-Being among Local State University of Cavite
Authors: Quiza Pearl Senilla, Hannah Mercado, Francis Angelo Erosa
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Underdog narratives not only provides viewers with models of determination and hard work but that inducing hope may increase the likelihood that viewers will pursue their own goals in life. Although it has been proven that underdog narratives not only create a positive motivational state to the viewers but can also induce hope, little attention has been given to know if this underdog narrative affect the health outcomes or the subjective well-being of the viewers and if their hopefulness mediates on it. To address this gap, using underdog narratives as a predictor and hope as mediator, this study determined the effect of underdog narratives to the subjective well-being of the respondents, the relationship of hope and subjective well-being and last is the mediating effect of hopefulness. This study is an experimental research that uses a between subject design. Purposeful random sampling was used wherein the respondents must meet the following criteria to be part of the study. One hundred and twenty (N=120) Local State University students were assigned to different treatment conditions— underdog narrative, comedy, nature scenes—and a no exposure control group. Results show that there is a minimal difference on the subjective well-being of the respondents when exposed to different treatment condition although it is not significant. A moderate positive correlation between hope and subjective well-being also reveals in this study. And last the result also shows that there is no mediating effect of hopefulness to the subjective well-being of the subjects through exposure to underdog narrative.Keywords: hope, hope theory, subjective well-being, underdog narratives
Procedia PDF Downloads 31014786 Effect of Concrete Waste Quality on the Compressive Strength of Recycled Concrete
Authors: Kebaili Bachir
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The reuse of concrete waste as a secondary aggregate could be an efficient solution for sustainable development and long-term environmental protection. The variable nature of waste concrete, with various compressive strengths, can have a negative effect on the final compressive strength of recycled concrete. Accordingly, an experimental test programme was developed to evaluate the effect of parent concrete qualities on the performance of recycled concrete. Three grades with different compressive strengths 10MPa, 20MPa, and 30MPa were considered in the study; moreover, an unknown compressive strength was introduced as well. The trial mixes used 40% secondary aggregates (both course and fine) and 60% of natural aggregates. The compressive strength of the test concrete decrease between 15 and 25% compared to normal concrete with no secondary aggregates. This work proves that the strength properties of the parent concrete have a limited effect on the compressive strength of recycled concrete. Low compressive strength parent concrete when crushed generate a high percentage of recycled coarse aggregates with the less attached mortar and give the same compressive strength as an excellent parent concrete. However, the decrease in compressive strength can be mitigated by increasing the cement content 4% by weight of recycled aggregates used.Keywords: compressive, concrete, quality, recycled, strength
Procedia PDF Downloads 32714785 Numerical Study of a Nanofluid in a Truncated Cone
Authors: B. Mahfoud, A. Bendjaghlouli
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Natural convection is simulated in a truncated cone filled with nanofluid. Inclined and top walls have constant temperature where the heat source is located on the bottom wall of the conical container which is thermally insulated. A finite volume approach is used to solve the governing equations using the SIMPLE algorithm for different parameters such as Rayleigh number, inclination angle of inclined walls of the enclosure and heat source length. The results showed an enhancement in cooling system by using a nanofluid, when conduction regime is assisted. The inclination angle of inclined sidewall and heat source length affect the heat transfer rate and the maximum temperature.Keywords: heat source, truncated cone, nanofluid, natural convection
Procedia PDF Downloads 30814784 A New Type Safety-Door for Earthquake Disaster Prevention: Part I
Authors: Daniel Y. Abebe, Jaehyouk Choi
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From the past earthquake events, many people get hurt at the exit while they are trying to go out of the buildings because of the exit doors are unable to be opened. The door is not opened because it deviates from its the original position. The aim of this research is to develop and evaluate a new type safety door that keeps the door frame in its original position or keeps its edge angles perpendicular during and post-earthquake. The proposed door is composed of three components: outer frame joined to the wall, inner frame (door frame) and circular hollow section connected to the inner and outer frame which is used as seismic energy dissipating device.Keywords: safety-door, earthquake disaster, low yield point steel, passive energy dissipating device, FE analysis
Procedia PDF Downloads 52614783 Neuroprotective Effect of Germinated Dolichos lablab on 6-Hydroxy Dopamine (6-OHDA) Induced Toxicity in SH-SY5Y Neuroblastoma Cell
Authors: Taek Hwan Lee, Moon Ho Do, Lalita Subedi, Young Un Park, Sun Yeou Kim
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Natural and artificial toxic substances namely neurotoxins induce the bitter effect in the nervous system termed as neurotoxicity. It can modulate the normal functioning of the nervous system either hyperactivate it or damage homeostasis of neuronal system. Neurotoxins induced toxicity ultimately kills the neuron. The present study investigated the neuroprotective effects of germinated Dolichos lablab on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity using SH-SY5Y neuroblastoma cells. Germination is a process of plant growth from a seed. Sprouting of a seedling from a seed induced many molecular changes in the seed in order to prepare it for further growth. Because of these molecular and chemical changes, the neuroprotective effect of Dolichos lablab is higher in the germinated form than in the normal condition. SH-SY5Y cells were treated with Dolichos lablab extract (50, 100 g/ml) followed by 6-OHDA (25M) induced toxicity. Cell Viability was measured to check the cell survival against 6-OHDA induced toxicity using MTT assay. Dolichos lablab showed a neuroprotective effect against 6-OHDA induced neuronal cell death in neuroblastoma cell at a higher concentration of 100g/ml however the effect is much better even at the lower concentration after germination 50g/ml. Cell survival was increased dramatically after 15 h of germination and increased with time of germination in concentration dependent manner. Trigonelline as a representative compound was validated in germinated Dolichos lablab by HPLC analysis that might enhance the neuroprotective effect of Dolichos lablab. This result suggests that Dolichos lablab possess neuroprotective effect in neuroblastoma cells against 6-OHDA however its activity was more potent in the germinated form.Keywords: dolichos lablab, germination, neuroprotection, trigonelline
Procedia PDF Downloads 32314782 The Effect of Meteorological Factors on the Trap Catches of Culicoides Species
Authors: Ahmed M. Rashed
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Culicoides midges are known to be vectors of disease to both man and animals. For providing information necessary for control methods to be applied to the best advantage, a New jersey light-trap was used. Twenty species were identified during this study and eight species were recorded from Chantilly for the first time, these include C.grisescens, C.nubeculosus, C.cubitalis, C.achrayi, C.circumscriptus, C.stigma, C.reconditus, and C.parroti. The environmental factors, wind speed and temperature were found to have a marked effect on the activity of Culicoides midges. The temperature was found to be positively correlated and the wind speed negatively correlated with the light-trap catch. However, humidioty could not be shown to have any effect on the catch.Keywords: culicoides, meteorological factors, wind speed, disease
Procedia PDF Downloads 45214781 Effect of Interlayer Coupling in Co/Al2O3/Co
Authors: Niru Chowdhury, Subhankar Bedanta, Alexander Weber, Thomas Brueckel
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We show the effect of interlayer coupling on magnetization reversal in purely dipolar coupled magnetic multilayers. Longitudinal magneto-optic Kerr microscopy (LMOKE) has been performed on [Co(10nm)/Al2O3(t)/Co(10nm)] for various thicknesses of Al2O3(t). We will show that inter-layer coupling interactions lead to layer-by-layer reversal in the magnetic multilayers. Also transverse component of magnetization was observed for higher thickness of the spacer layer.Keywords: Interlayer coupling, Magnetic domains, Magneto – Optic Kerr effect microscopy, Magnetization reversal, Magnetic thin film
Procedia PDF Downloads 39914780 Research on the Effect of the System of General Counsel on the Efficiency of M&As in State-Owned Enterprises
Authors: Mao Ju
Abstract:
The system of general counsel (GC) is an important governance structure designed for the construction of state-owned enterprises (SOEs) under the rule of law. This article is based on the setting of mergers and acquisitions (M&As) and takes the efficiency of M&As to examine the implementation effect of the system of GC for SOEs. Research has found that: (1) companies implementing the system of GC for SOEs have higher efficiency in M&As, manifested in better operational and market performance, and this effect depends on the professional ability and power of the GC. This indicates that the GC of SOEs has played a positive role in the decision-making process of M&As, which helps to improve the efficiency of M&As. (2) The impact of the GC of SOEs on the efficiency of M&As is heterogeneous, and this positive effect is mainly reflected in local and commercial SOEs. (3) The path of this impact is that the GC of SOEs can help reduce ineffective M&As in advance, enhance the ability to integrate M&As after the fact and reduce the risk of goodwill impairment and bankruptcy. This article reveals the impact of the construction of SOEs under the rule of law with the system of GC as the core of M&As activities, providing intuitive evidence for the implementation effect of the GC of SOEs. The research conclusion has important practical guiding value for comprehensively deepening the construction of the rule of SOEs under the rule of law and writing a good chapter on the Chinese path to modernization of SOEs.Keywords: the system of general counsel, merger and acquisition efficiency, state-owned enterprises, mergers and acquisitions
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