Search results for: free moving particles

Authors: Han Longxiang

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In the process of treating industrial oily wastewater with complex components, the traditional treatment methods (flotation, coagulation, microwave heating, etc.) often produce high operating costs, secondary pollution, and other problems. In order to solve these problems, the materials with high flux and stability applied to surfactant-stabilized emulsions separation have gained huge attention in the treatment of oily wastewater. Nevertheless, four stable oil-in-water emulsions can be formed due to different surfactants (surfactant-free, anionic surfactant, cationic surfactant, and non-ionic surfactant), and the previous advanced materials can only separate one or several of them, cannot effectively separate in one step. Herein, a facile synthesis method of graphene-based multilevel filter materials (GMFM) which can efficiently separate the oil-in-water emulsions stabilized with different surfactants only through its gravity. The prepared materials with high stability of 20 cycles show a high flux of ~ 5000 L m-2 h-1 with a high separation efficiency of > 99.9 %. GMFM can effectively separate the emulsion stabilized by mixed surfactants and oily wastewater from factories. The results indicate that the GMFM have a wide range of applications in oil-in-water emulsions separation in industry and environmental science.

Keywords: emulsion, filtration, graphene, one-step

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Authors: Violeta Damjanovic-Behrendt

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This paper presents an approach for optimal cyber security decisions to protect instances of a federated Internet of Things (IoT) platform in the cloud. The presented solution implements the repeated Stackelberg Security Game (SSG) and a model called Stochastic Human behaviour model with AttRactiveness and Probability weighting (SHARP). SHARP employs the Subjective Utility Quantal Response (SUQR) for formulating a subjective utility function, which is based on the evaluations of alternative solutions during decision-making. We augment the repeated SSG (including SHARP and SUQR) with a reinforced learning algorithm called Naïve Q-Learning. Naïve Q-Learning belongs to the category of active and model-free Machine Learning (ML) techniques in which the agent (either the defender or the attacker) attempts to find an optimal security solution. In this way, we combine GT and ML algorithms for discovering optimal cyber security policies. The proposed security optimization components will be validated in a collaborative cloud platform that is based on the Industrial Internet Reference Architecture (IIRA) and its recently published security model.

Keywords: security, internet of things, cloud computing, stackelberg game, machine learning, naive q-learning

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Authors: Marouen Hamdi, Johannes A. Poulis

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This study investigates the impact of UV/ozone treatment on the adhesion of ethylene propylene diene methylene (EPDM) rubber, polyvinyl chloride (PVC), and acrylonitrile butadiene styrene (ABS) materials. The experimental tests consist of contact angle measurements, standardized adhesion tests, and spectroscopic and microscopic observations. Also, commonly-used surface free energy models were applied to characterize the wettability of the materials. Preliminary results show that the treatment enhances the wettability of the examined polymers. Also, it considerably improved the adhesion strength of PVC and ABS and shifted their failure modes from adhesive to cohesive, without a significant effect on EPDM. Spectroscopic characterization showed significant oxidation-induced changes in the chemical structures of treated PVC and ABS surfaces. Also, new morphological changes (microcracks, micro-holes, and wrinkles) were observed on these two materials using the SEM. These chemical and morphological changes on treated PVC and ABS promote more reactivity and mechanical interlocking with the adhesive, which explains the improvement in their adhesion strength. After characterizing the adhesion strength of the systems, accelerated ageing tests in controlled environment chambers will be conducted to determine the effect of temperature, moisture, and UV radiation on the performance of the polymeric bonded joints.

Keywords: accelerated tests, adhesion strength, ageing of polymers, UV/ozone treatment

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Authors: Y. Pilehvar-Soltanahmadi, F. Badrzadeh, N. Zarghami, S. Jalilzadeh-Tabrizi, R. Zamani

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Herbal compounds such as curcumin which decrease telomerase and gene expression have been considered as beneficial tools for lung cancer treatment. In this article, we compared the effects of pure curcumin and curcumin-loaded NIPAAm-MAA nanoparticles on telomerase and PinX1 gene expression in a lung cancer cell line. A tetrazolium-based assay was used for determination of cytotoxic effects of curcumin on the Calu-6 lung cancer cell line and telomerase and pinX1 gene expression was measured with real-time PCR. MTT assay showed that Curcumin-loaded NIPAAm-MAA inhibited the growth of the Calu-6 lung cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of curcumin-loaded NIPAAm-MAA increased while expression of the PinX1 gene became elevated. The results showed that curcumin loaded NIPAAm-MAA exerted cytotoxic effects on the Calu-6 cell line through down-regulation of telomerase and stimulation of pinX1 gene expression. NIPPAm-MAA could be the good carrier for such kinds of hydrophobic agent.

Keywords: curcumin, NIPAAm-MAA, PinX1, telomerase, lung cancer cells

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Authors: Andrew R. Winters, Gregor J. Gassner

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A high-order numerical magentohydrodynamics (MHD) solver built upon a non-linear entropy stable numerical flux function that supports eight traveling wave solutions will be described. The method is designed to treat the divergence-free constraint on the magnetic field in a similar fashion to a hyperbolic divergence cleaning technique. The solver is especially well-suited for flows involving strong discontinuities due to its strong stability without the need to enforce artificial low density or energy limits. Furthermore, a new formulation of the numerical algorithm to guarantee positivity of the pressure during the simulation is described and presented. By construction, the solver conserves mass, momentum, and energy and is entropy stable. High spatial order is obtained through the use of a third order limiting technique. High temporal order is achieved by utilizing the family of strong stability preserving (SSP) Runge-Kutta methods. Main attributes of the solver are presented as well as details on an implementation of the new solver into the multi-physics, multi-scale simulation code FLASH. The accuracy, robustness, and computational efficiency is demonstrated with a variety of numerical tests. Comparisons are also made between the new solver and existing methods already present in FLASH framework.

Keywords: entropy stability, finite volume scheme, magnetohydrodynamics, pressure positivity

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Authors: Daniel F. Sava, Anton Ficai, Bogdan S. Vasile, Georgeta Voicu, Ecaterina Andronescu

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The energy crisis and environmental contamination are very serious problems, therefore searching for better and sustainable renewable energy is a must. It is predicted that the global energy demand will double until 2050. Solar water splitting and photocatalysis are considered as one of the solutions to these issues. The use of oxide semiconductors for solar water splitting and photocatalysis started in 1972 with the experiments of Fujishima and Honda on TiO2 electrodes. Since then, the evolution of nanoscience and characterization methods leads to a better control of size, shape and properties of materials. Although the past decade advancements are astonishing, for these applications the properties have to be controlled at a much finer level, allowing the control of charge-carrier lives, energy level positions, charge trapping centers, etc. Graphene has attracted a lot of attention, since its discovery in 2004, due to the excellent electrical, optical, mechanical and thermal properties that it possesses. These properties make it an ideal support for photocatalysts, thus graphene composites with oxide semiconductors are of great interest. We present in this work the synthesis and characterization of graphene-related materials and oxide semiconductors and their different composites. These materials can be used in constructing devices for different applications (batteries, water splitting devices, solar cells, etc), thus showing their application flexibility. The synthesized materials are different morphologies and sizes of TiO2, ZnO and Fe2O3 that are obtained through hydrothermal, sol-gel methods and graphene oxide which is synthesized through a modified Hummer method and reduced with different agents. Graphene oxide and the reduced form could also be used as a single material for transparent conductive films. The obtained single materials and composites were characterized through several methods: XRD, SEM, TEM, IR spectroscopy, RAMAN, XPS and BET adsorption/desorption isotherms. From the results, we see the variation of the properties with the variation of synthesis parameters, size and morphology of the particles.

Keywords: composites, graphene, hydrothermal, renewable energy

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Authors: Poojan Kothari, Yash Madhani, Chayan Jani, Bharti Saini

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The requirements for quality drinking and industrial water are increasing and water resources are depleting. Moreover large amount of wastewater is being generated and dumped into water bodies without treatment. These have made improvement in water treatment efficiency and its reuse, an important agenda. Membrane technology for wastewater treatment is an advanced process and has become increasingly popular in past few decades. There are many traditional methods for tertiary treatment such as chemical coagulation, adsorption, etc. However recent developments in membrane technology field have led to manufacturing of better quality membranes at reduced costs. This along with the high costs of conventional treatment processes, high separation efficiency and relative simplicity of the membrane treatment process has made it an economically viable option for municipal and industrial purposes. Ultrafiltration polymeric membranes can be used for wastewater treatment and drinking water applications. The proposed work focuses on preparation of one such UF membrane - Polyvinylidene fluoride (PVDF) doped with LiBr for wastewater treatment. Majorly all polymeric membranes are hydrophobic in nature. This property leads to repulsion of water and hence solute particles occupy the pores, decreasing the lifetime of a membrane. Thus modification of membrane through addition of small amount of salt such as LiBr helped us attain certain characteristics of membrane, which can then be used for wastewater treatment. The membrane characteristics are investigated through measuring its various properties such as porosity, contact angle and wettability to find out the hydrophilic nature of the membrane and morphology (surface as well as structure). Pure water flux, solute rejection and permeability of membrane is determined by permeation experiments. A study of membrane characteristics with various concentration of LiBr helped us to compare its effectivity.

Keywords: Lithium bromide (LiBr), morphology, permeability, Polyvinylidene fluoride (PVDF), solute rejection, wastewater treatment

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Authors: Adesoji Sodeinde

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Analytical derivatives has recently undergone an explosive growth in areas of separation techniques, likewise in detectability of certain compound/concentrated ions. The gloomy and depressing scenario which charaterized the application of analytical derivatives in areas of water analysis, water cycle and the environment should not be allowed to continue unabated. Due to technological advancement in various chemical/biochemical analysis separation techniques is widely used in areas of medical, forensic and to measure and assesses environment and social-economic impact of alternative control strategies. This technological improvement was dully established in the area of comparison between certain separation/detection techniques to bring about vital result in forensic[as Gas liquid chromatography reveals the evidence given in court of law during prosecution of drunk drivers]. The water quality analysis,pH and water temperature analysis can be performed in the field, the concentration of dissolved free amino-acid [DFAA] can also be detected through separation techniques. Some important derivatives/ions used in separation technique. Water analysis : Total water hardness [EDTA to determine ca and mg ions]. Gas liquid chromatography : innovative gas such as helium [He] or nitrogen [N] Water cycle : Animal bone charcoal,activated carbon and ultraviolet light [U.V light].

Keywords: analytical derivative, environment, water analysis, chemical/biochemical analysis

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Authors: Md. Imran H. Khan, T. Farrell, M. A. Karim

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Highly porous and hygroscopic characteristics of pear make it complex to understand the cellular level water distribution. In pear tissue, water is mainly distributed in three different spaces namely, intercellular water, intracellular water, and cell wall water. Understanding of these three types of water in pear tissue is crucial for predicting actual heat and mass transfer during drying. Therefore, the aim of the present study was to investigate the proportion of intercellular water, intracellular water, and cell wall water inside the pear tissue. During this study, Green Anjou Pear was taken for the investigation. The experiment was performed using 1H-NMR- T2 relaxometry. Various types of water component were calculated by using multi-component fits of the T2 relaxation curves. The experimental result showed that in pear tissue 78-82% water exist in intracellular space; 12-16% water in intercellular space and only 2-4% water exist in the cell wall space. The investigated results quantify different types of water in plant-based food tissue. The highest proportion of water exists in intracellular spaces. It was also investigated that the physical properties of pear and the proportion of the different types of water has a strong relationship. Cell wall water depends on the proportion of solid in the sample tissue whereas free water depends on the porosity of the material.

Keywords: intracellular water, intercellular water, cell wall water, physical property, pear

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Authors: Ilhan Keskin, Hasan Bulent Kantarci

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In this study, one of the tools of Islamic financing known as “Sukuk” a non-interest bearing investment which has started to be implemented in Turkey and the world as a whole is discussed. In order to increase the vitality and efficiency of the economy, by taking lessons from the recent economic crisis new developments in the banking and investment sector are being expanded. The purpose of all investors is to obtain more revenue through the use of capital. The inability of traditional investment tools to meet the expectations of investors and the interest based financial system where one investor benefits at the expense of another there has been the need for a different, reliable and non-interest bearing financial market that is consistent with the Islamic rule. As a result an alternative and more reliable interest free financing tool “Sukuk” rental certificates covering people who are sensitive to Islamic rules, appeal to all segments, hidden remaining capital that contributes to the economy, reduce disparities in income distribution, common risk sharing system of profit and loss sharing has emerged. Today, for the structural countries by examining the state of the world market economy the applicability, enactment and future issues associated with this attractive kind of Islamic finance namely the “Sukuk” market has been explained.

Keywords: Islamic finance, islamic markets, non-interest bearing, rental certificates

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Authors: Karolína Augustovaá

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Turkey’s eastern borders have been at the center of criticism by the European Commission who condemns restrictions against Kurdish civilians as the result of Turkey’s military operations against terrorist organizations (namely PKK). Yet, the Commission has launched economic and political support for numerous military projects along the Iran-Turkey border to fight cross-border crime (namely “illegal” migration) along its external borders. Whilst border externalization has been extensively examined in the EU’s wide neighborhood, its analysis from the ground in conflict zones is emerging. The existing analysis also rarely considers the impact of external border management beyond international migration - on the local context and its people. However, tough externalization policies at borders, where local wars are fought, are fundamental to scrutinize as they invite us to question the effects of EU’s migration management on diverse communities navigating their life along external borders. To fill this research lacunae, this article examines intersections between the local military operations and international (EU-Turkey) migration management at the Turkey’s border with Iran and questions their impact on the everyday struggles of people living at and migrating across the border. To do so, it applies critical feminist and military literature to border studies. Methodologically, the article draws upon ethnographic research in Van (Eastern Turkey), using participant observations and interviews with sixty participants. This article argues that the EU’s externalization policies add to the violence generated by the local militarized conflict and eventually (re-)produce it in the forms of push-backs and physical violence against people who daily cross the border irregularly for their physical/economic survival. By doing so, I suggest that (inter)national fears of terrorism and migration inter-sect, materialize and affect everyday sites of diverse racialized groups living at and moving across external borders, such as international migrants (Afghans) and the local residents (Kurds) at the Turkey-Iran border. This article highlights the need to analyze the local border context in tandem with international migration management in the EU’s wider neighborhood to understand how conflict and violence evolves there.

Keywords: european union border externalization, eastern turkey, migration, conflict, kurdish question

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Authors: Atefe Malekkhani, Lee Beattie, Mohsen Mohammadzadeh

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Rapid urbanization and the growth of megacities have resulted in numerous risks, concerns, and problems across various aspects of urban life, including environmental, social, and economic domains. Cities and regions are inevitably moving toward urban digitalization owing to the fast-paced development of information and communication technologies (ICTs). The concept of 'smart city' represents an emerging solution to urban challenges arising from increased urbanization using ICTs. However, smart cities are often perceived primarily as technological initiatives and are implemented without considering the social and cultural contexts of cities and the needs of their residents. The implementation of smart city projects and initiatives has the potential to (un)intentionally exacerbate pre-existing social, spatial, and cultural segregation. Investigating the impact of smart city on social capital of people who are users of smart city systems and with governance as policymakers is worth exploring. 'Social capital' defined as the network of relationships and resources available to individuals through social interactions, is a glue that binds the community together. It is also a resource that benefits society by representing the collective amount of civic engagement, communal values, and interpersonal trust within a given geographic region or political entity. Despite the existing theoretical and practical knowledge, there is a significant research gap concerning the role and impact of smart city infrastructure in building social capital. Currently, there is no conclusive evidence indicating whether the impact of smart city infrastructure on social capital is positive or negative or to what extent smart city infrastructure can foster social capital in communities and cities. To shed light on this issue, this study aims to explore the domain of existing research in the field of smart city through the lens of social capital. This research will use the 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' (PRISMA) method to review relevant literature, focusing on the key concepts of 'Smart City' and 'Social Capital'. The studies will be selected Web of Science Core Collection, using a selection process that involves identifying literature sources, screening and filtering studies based on titles, abstracts, and full-text reading.

Keywords: Smart city, urban digitalisation, ICT, social capital

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Authors: Fares A. Mayia, Mahmoud A. Yamany, Mushabbab A. Asiri

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In recent years, non-invasive Focused Ultrasound (FU) has been utilized for generating bubbles (cavities) to ablate target tissue by mechanical fractionation. Intensities >10 kW/cm² are required to generate the inertial cavities. The generation, rapid growth, and collapse of these inertial cavities cause tissue fractionation and the process is called Histotripsy. The ability to fractionate tissue from outside the body has many clinical applications including the destruction of the tumor mass. The process of tissue fractionation leaves a void at the treated site, where all the affected tissue is liquefied to particles at sub-micron size. The liquefied tissue will eventually be absorbed by the body. Histotripsy is a promising non-invasive treatment modality. This paper presents a technique for generating inertial cavities at lower intensities (< 1 kW/cm²). The technique (patent pending) is based on amplitude modulation (AM), whereby a low frequency signal modulates the amplitude of a higher frequency FU wave. Cavitation threshold is lower at low frequencies; the intensity required to generate cavitation in water at 10 kHz is two orders of magnitude lower than the intensity at 1 MHz. The Amplitude Modulation technique can operate in both continuous wave (CW) and pulse wave (PW) modes, and the percentage modulation (modulation index) can be varied from 0 % (thermal effect) to 100 % (cavitation effect), thus allowing a range of ablating effects from Hyperthermia to Histotripsy. Furthermore, changing the frequency of the modulating signal allows controlling the size of the generated cavities. Results from in vitro work demonstrate the efficacy of the new technique in fractionating soft tissue and solid calcium carbonate (Chalk) material. The technique, when combined with MR or Ultrasound imaging, will present a precise treatment modality for ablating diseased tissue without affecting the surrounding healthy tissue.

Keywords: focused ultrasound therapy, histotripsy, inertial cavitation, mechanical tissue ablation

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Authors: Elena G. Salina, Vadim A. Makarov

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With the emergence of primary resistance to the current drugs and wide distribution of latent tuberculosis infection, a need for new compounds with a novel mode of action is growing steadily. Copper-mediated innate immunity and antibacterial toxicity propose novel strategies in TB drug discovery and development. Transcriptome of M. tuberculosis was obtained by RNA-seq, intracellular copper content was measured by ISP MS and complexes of 1-hydroxy-2-thiopyridines with copper were detected by HPLC.1-hydroxy-2-thiopyridine derivatives were found to be highly active in vitro against both actively growing and dormant non-culturable M. tuberculosis. Transcriptome response to 1-hydroxy-2-thiopyridines revealed signs of copper toxicity in M. tuberculosis bacilli. Indeed, Cu was found to accumulate inside cells treated with 1-hydroxy-2-thiopyridines. These compounds were found to form stable charged lipophylic complexes with Cu²⁺ ions which transport into mycobacterial cell. Subsequent metabolic destruction of the complex led to transformation of 1-hydroxy-2-thiopyridines into 2-methylmercapto-2-ethoxycarbonylpyridines, which did not possess antitubercular activity and releasing of free Cu²⁺ in the cytoplasm. 1-hydroxy-2-thiopyridines are a potent class of Cu-dependent inhibitors of M. tuberculosis which may control M. tuberculosis infection by impairment of copper homeostasis. Acknowledgment: This work was financially supported by the Ministry of Education and Science of the RussianFederation (Agreement No 14.616.21.0065; unique identifier RFMEFI61616X0065).

Keywords: copper toxicity, drug discovery, M. tuberculosis inhibitors, 2-thiopyridines

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Authors: A. Nkohla, U. Nwodo, L. V. Mabinya, A. I. Okoh

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A potential source for low-cost production of value added products is the utilization of lignocellulosic materials. However, the huddle needing breaching would be the dismantlement of the complex lignocellulosic structure as to free sugar base therein. the current lignocellosic material treatment process is expensive and not eco-friendly hence, the advocacy for enzyme based technique which is both cheap and eco-friendly is highly imperative. Consequently, this study aimed at the screening of cellulose and xylan degrading bacterial strain isolated from decaying sawdust samples. This isolate showed high activity for cellulase and xylanase when grown on carboxymethyl cellulose and birtchwood xylan as the sole carbon source respectively. The 16S rDNA nucleotide sequence of the isolate showed 98% similarity with that of Chryseobacterium taichungense thus, it was identified as a Chryseobacterium sp. Optimum culture conditions for cellulase and xylanase production were medium pH 6, incubation temperature of 25 °C at 50 rpm and medium pH 6, incubation temperature of 25 °C at 150 rpm respectively. The high enzyme activity obtained from this bacterial strain portends it as a good candidate for industrial use in the degradation of complex biomass for value added products.

Keywords: lignocellulosic material, chryseobacterium sp., submerged fermentation, cellulase, xylanase

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Authors: P. A. Broodryk, A. F. Van Der Merwe, H. W. J. P. Neomagus

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The production of the clear liquid fertilizer ammonium polyphosphate (APP) is best achieved by the pyrolysis of urea phosphate, as it produces a product that is free from any of the impurities present in the raw phosphoric acid it was made from. This is a multiphase, multi-step reaction that produces carbon dioxide and ammonia as gasses and ammonium polyphosphate as liquid products. The polyphosphate chain length affects the solubility and thus the applicability of the product as liquid fertiliser, thus proper control of the reaction conditions is thus required for the use of this reaction in the production of fertilisers. This study investigates the reaction kinetics of the aforementioned reaction, describing a mathematical model for the kinetics of the reaction along with the accompanying rate constants. The reaction is initially exothermic, producing only carbon dioxide as a gas product and ammonium diphosphate, at higher temperatures the reaction becomes endothermic, producing ammonia gas as an additional by-product and longer chain polyphosphates, which when condensed too far becomes highly water insoluble. The aim of this study was to (i) characterise the pyrolysis reaction of urea phosphate by determining the mechanisms and the associated kinetic constants, and (ii) to determine the optimum conditions for ammonium diphosphate production. A qualitative investigation was also done to find the rate of hydrolysis of APP as this provides an estimate of the shelf life of an APP clear liquid fertiliser solution.

Keywords: ammonium polyphosphate, kinetics, pyrolysis, urea phosphate

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Authors: Gurmeet Singh Cheema, Gurjinder Singh, Amardeep Singh Kang

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Aluminium alloy 6061 is a medium to high strength heat-treatable alloy which has very good corrosion resistance and very good weldability. Friction Stir Welding was developed and this technique has attracted considerable interest from the aerospace and automotive industries since it is able to produce defect free joints particularly for light metals i.e aluminum alloy and magnesium alloy. In the friction stir welding process, welding parameters such as tool rotational speed, welding speed and tool shoulder diameter play a major role in deciding the weld quality. In this research work, an attempt has been made to understand the effect of tool rotational speed, welding speed and tool shoulder diameter on friction stir welded AA6061 aluminium alloy joints. Statistical tool such as central composite design is used to develop the mathematical relationships. The mathematical model was developed to predict mechanical properties of friction stir welded aluminium alloy joints at the 95% confidence level.

Keywords: aluminium alloy, friction stir welding, central composite design, mathematical relationship

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Authors: Shuwen Wu, Zhi LI

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Atomically dispersed Fe‒N₄ catalysts are proven as promising alternatives to commercial Pt/C for the oxygen reduction reaction. Most reported Fe‒N₄ catalysts suffer from inferior O‒O bond-breaking capability due to superoxo-like O₂ adsorption, though the isolated dual-atomic metal sites strategy is extensively adopted. Atomic Fe clusters hold greater promise for promoting O‒O bond cleavage by forming peroxo-like O₂ adsorption. However, the excessively strong binding strength between Fe clusters and oxygenated intermediates sacrifices the activity. Here, we first report a Fex/Cu‒N@CF catalyst with atomic Fe clusters functionalized by adjacent single Cu‒N₄ sites anchoring on a porous carbon nanofiber membrane. The theoretical calculation indicates that the single Cu‒N₄ sites can modulate the electronic configuration of Fe clusters to reduce O₂* protonation reaction free energy, which ultimately enhances the electrocatalytic performance. Particularly, the Cu‒N₄ sites can increase the overlaps between the d orbitals of Fe and p orbitals of O to accelerate O‒O cleavage in OOH*. As a result, this unique atomic catalyst exhibits a half potential (E1/2) of 0.944 V in an alkaline medium exceeding that of commercial Pt/C, whereas acidic performance E1/2 = 0.815 V is comparable to Pt/C. This work shows the great potential of single atoms for improvements in atomic cluster catalysts.

Keywords: Hierarchical porous fibers, atomic Fe clusters, Cu single atoms, oxygen reduction reaction; O-O bond cleavage

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Authors: Shailendra Kumar Singh

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In the 21st century, we are living through extraordinary times as we are linguistically blessed to live through an era in which the each sociolinguistic example of living appears to be refreshingly new without any precedence of the past. The word `New Linguistic World Order’ is no longer just the intangible fascination but an indication of the emerging reality that we are living through a time in which the word ‘linguistic purism’ no longer invokes the sense of self categorization and self identification. The contemporary world of today is linguistically rewarding. This is a time in which the very existence of global, powerful and local needs to be revisited in the context of power shift, demographic shift, social psychological shift and technological shift. Hence, the old linguistic world view has to be challenged in the midst of 21st century. The first years of the 21st century have thus far been marked by the rise global economy, technological revolution and demographic shift, now we are witnessing linguistic shift which is leading towards forming a new linguistic world order. On the other hand, with rising powers of China and India in Asia in tandem the notion of alternative west is set to become a lot more interesting linguistically. It comes at a point when the world is moving towards inclusive globalization due to vanishing power corridor of the west and ascending geopolitical impact of emerging superpower and superpower in waiting. Now it is a reality that the western world no longer continues to rise – in fact, it will have more pressure to act in situation when the alternative west is looking for balanced globalization. It is more than likely that demographically strong languages of alternative west will be in advantageous position. The paper challenges our preconceptions about the nature of sociolinguistic nature of world in the 21st century. It investigates what a linguistic world is likely to be in the future in contrast to what was a linguistic world before 21st century. In particular, the paper tries to answer the following questions: (a) What will be the common linguistic thread across world? (b) How unprecedented transformations can be mapped linguistically? (c) Do we need alternative linguistics to define inclusive globalization as the linguistic reality of the contemporary world has already been reshaped by increasingly integrated world economy, linguistic revolution and alternative west? (d) In which ways these issues can be addressed holistically? (e) Why linguistic world order is changing dramatically? (f) Is it true that the linguistic world around is changing faster than we can even really cope? (g) Is it true that what is coming next is linguistically greater than ever? (h) Do we need to prepare ourselves with new theoretical strategies to address emerging sociolinguistic reality?

Keywords: alternative linguistics, new linguistic world order, power shift, demographic shift, social psychological shift, technological shift

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Authors: Raúl Jiménez Vilches

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Native (L1) speakers can mark prosodically one part of an utterance and make it more relevant as opposed to the rest of the constituents. Conversely, non-native (L2) speakers encounter problems when it comes to marking prosodically information structure in English. In fact, the L2 speaker’s choice for the prosodic realization of focus is not so clear and often obscures the intended pragmatic meaning and the communicative value in general. This paper reports some of the findings obtained in an L2 prosodic training course for Spanish learners of English within the context of public speaking. More specifically, it analyses the effects of the course experiment in relation to the non-native production of the tonic syllable to mark focus and compares it with the public speeches delivered by native English speakers. The whole experimental training was executed throughout eighteen input sessions (1,440 minutes total time) and all the sessions took place in the classroom. In particular, the first part of the course provided explicit instruction on the recognition and production of the tonic syllable and how the tonic syllable is used to express focus. The non-native and native oral presentations were acoustically analyzed using Praat software for speech analysis (7,356 words in total). The investigation adopted mixed and embedded methodologies. Quantitative information is needed when measuring acoustically the phonetic realization of focus. Qualitative data such as questionnaires, interviews, and observations were also used to interpret the quantitative data. The embedded experiment design was implemented through the analysis of the public speeches before and after the intervention. Results indicate that, even after the L2 prosodic training course, Spanish learners of English still show some major inconsistencies in marking focus effectively. Although there was occasional improvement regarding the choice for location and word classes, Spanish learners were, in general, far from achieving similar results to the ones obtained by the English native speakers in the two types of focus. The prosodic realization of focus seems to be one of the hardest areas of the English prosodic system to be mastered by Spanish learners. A funded research project is in the process of moving the present classroom-based experiment to an online environment (mobile app) and determining whether there is a more effective focus usage through CAPT (Computer-Assisted Pronunciation) tools.

Keywords: focus, prosody, public speaking, Spanish learners of English

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Authors: Pornthep Rachnavy

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The purpose of this paper is twofold. First, we believe that there are a significant relationship between sculling angle and sculling style among adaptive rowing. Second, we introduce a methodology used for adaptive rowing, namely simulation, to identify effectiveness of adaptive rowing. For our study we simulate the arms only single scull of adaptive rowing. The method for rowing fastest under the 1000 meter was investigated by study sculling angle using the simulation modeling. A simulation model of a rowing system was developed using the Matlab software package base on equations of motion consist of many variation for moving the boat such as oars length, blade velocity and sculling style. The boat speed, power and energy consumption on the system were compute. This simulation modeling can predict the force acting on the boat. The optimum sculling angle was performing by computer simulation for compute the solution. Input to the model are sculling style of each rower and sculling angle. Outputs of the model are boat velocity at 1000 meter. The present study suggests that the optimum sculling angle exist depends on sculling styles. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the first style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the second style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the third style is -51.57 and 28.65 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the fourth style is -45.84 and 34.38 degree. A theoretical simulation for rowing has been developed and presented. The results suggest that it may be advantageous for the rowers to select the sculling angles proper to sculling styles. The optimum sculling angles of the rower depends on the sculling styles made by each rower. The investigated of this paper can be concludes in three directions: 1;. There is the optimum sculling angle in arms only single scull of adaptive rowing. 2. The optimum sculling angles depend on the sculling styles. 3. Computer simulation of rowing can identify opportunities for improving rowing performance by utilizing the kinematic description of rowing. The freedom to explore alternatives in speed, thrust and timing with the computer simulation will provide the coach with a tool for systematic assessments of rowing technique In addition, the ability to use the computer to examine the very complex movements during rowing will help both the rower and the coach to conceptualize the components of movements that may have been previously unclear or even undefined.

Keywords: simulation, sculling, adaptive, rowing

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Authors: Naseem Akhter, Rozina Khattak, Arshad Munir

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The Islamic social and family system is very clear concerning will, choice, consent and negation of compulsion and force in human life. Marriage is not only a civil contract but also a religious and spiritual contract between spouse (man and woman), which allows them for each other to live gladly, joyfully and legally in the society. It is an immortal and perpetual association between man and woman, which is filled with sympathetic affection, kindness, compassion and security. Islam gives specific rights to parents and guardians to set up the marriage ceremony and get done it as a respectful family occasion, confer their blessing and advice for a life partner of their children. The rights of parents and guardians are summed up in the term of "Willayah”. Islam does not permit parents, guardians and other relatives to compel their children regarding the marriage of their choice, because the groom and the bride are the real parties of the contract. Therefore, their willingness is of prime importance in order to spend whole life with each other. The Holy Prophet (peace and blessings of Allah be upon him) prohibits forcing a virgin to marriage without her permission, whether this is her father or someone else. The right of free consent to choose a life partner is the basic right for the human which is God (Allah) gifted. Unfortunately, forced marriage is a common practice in Pakistani society that has no link with Islam. This article is being written in the same context.

Keywords: choice, consent, forced marriage, Islam, parents, spouse

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Authors: Riaz Ahmed Mangrio

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Reduplication in Urdu-Hindi affects all major word categories, particles, and even nonsensical words. It conveys a variety of meanings, including distribution, emphasis, iteration, adjectival and adverbial. This study will primarily discuss reduplicative structures of nonsensical words in Urdu-Hindi and then briefly look at some examples from other Indo-Aryan languages to introduce the debate regarding the same structures in them. The goal of this study is to present counter-evidence against Keane (2005: 241), who claims “the base in the cases of lexical and phrasal echo reduplication is always independently meaningful”. However, Urdu-Hindi reduplication derives meaningful compounds from nonsensical words e.g. gũ mgũ (A) ‘silent and confused’ and d̪əb d̪əb-a (N) ‘one’s fear over others’. This needs a comprehensive examination to see whether and how the various structures form patterns of a base-reduplicant relationship or, rather, they are merely sub lexical items joining together to form a word pattern of any grammatical category in content words. Another interesting theoretical question arises within the Optimality framework: in an OT analysis, is it necessary to identify one of the two constituents as the base and the other as reduplicant? Or is it best to consider this a pattern, but then how does this fit in with an OT analysis? This may be an even more interesting theoretical question. Looking for the solution to such questions can serve to make an important contribution. In the case at hand, each of the two constituents is an independent nonsensical word, but their echo reduplication is nonetheless meaningful. This casts significant doubt upon Keane’s (2005: 241) observation of some examples from Hindi and Tamil reduplication that “the base in cases of lexical and phrasal echo reduplication is always independently meaningful”. The debate on the point becomes further interesting when the triplication of nonsensical words in Urdu-Hindi e.g. aẽ baẽ ʃaẽ (N) ‘useless talk’ is also seen, which is equally important to discuss. The example is challenging to Harrison’s (1973) claim that only the monosyllabic verbs in their progressive forms reduplicate twice to result in triplication, which is not the case with the example presented. The study will consist of a thorough descriptive analysis of the data for the purpose of documentation, and then there will be OT analysis.

Keywords: reduplication, urdu-hindi, nonsensical, optimality theory

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Authors: M. P. E. E Silva, A. M. Galloway, A. I. Toumpis

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An increasing concern exists in the welding industry in terms of faster joining processes. Methods such as the alternation between shielding gases such Ar, CO₂ and He have been able to provide improved penetration of the joint, reduced heat transfer to the workpiece, and increased travel speeds of the welding torch. Nitrogen as a shielding gas is not desirable due to its reactive behavior within the arc plasma, being absorbed by the molten pool during the welding process. Below certain amounts, nitrogen is not harmful. However, the nitrogen threshold is reduced during the solidification of the joint, and if its subsequent desorption is not completed on time, gas entrapment and blowhole formation may occur. The present study expanded the use of the alternating shielding gas method in the gas metal arc welding (GMAW) process by alternately supplying Ar/5%N₂ and He. Improvements were introduced in terms of joint strength and grain refinement. Microstructural characterization findings showed porosity-free welds with reduced inclusion formation while mechanical tests such as tensile and bend tests confirmed the reinforcement of the joint by the addition of nitrogen. Additionally, significant reductions of the final distortion of the workpiece were found after the welding procedure as well as decreased heat affected zones and temperatures of the weld.

Keywords: alternating shielding gas method, GMAW, grain refinement, nitrogen, porosity, mechanical testing

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Authors: M. Meddi, A. Boufekane

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The Mitidja coastal groundwater which extends over an area of 1450 km2 is a strategic resource in the Algiers region. The high dependence of the regional economy on the use of this groundwater forces us to have recourse to its artificial recharge from the Wadi El Harrach in its upstream part. This system of artificial recharge has shown its effectiveness in the development of water resource mentioned in the succeeding works in several regions of the world. The objective of this study is to: Increase the reserves of water inputs by infiltration, raise the water level and its good quality in wells and boreholes, reduce losses to the sea, and address seawater intrusion by maintaining balance in the freshwater-saltwater interface in the downstream part of the groundwater basin. After analyzing the situation, it was noticed that a qualitative monitoring of the Wadi water for the groundwater recharge has to be done. For this purpose, we proceeded during three successive years (2010, 2011, and 2012) to the monthly sampling of water in the upstream part of the Wadi El Harrach for chemical analysis. The variation of the sediment transport concentration will be also measured. This monitoring aims to characterize the water quality and avoid clogging in the proposed recharge area. The results of these analyses showed the good chemical quality according to the analyses we performed in the laboratory during the three years, but they are too loaded with suspended matters. We noticed that these fine particles come from the grinding of limestone of sandpit located upstream of the area of the proposed recharge system. This problem can be solved by a water supply upstream of sandpit. For the recharge, we propose the method of using two wells for dual use, which means that it can be used for water supply and extraction. This solution is inexpensive in our case and could easily be used as wells are already drilled in the upstream part. This solution increases over time the piezometric level and also reduce groundwater contamination by saltwater in the downstream part.

Keywords: water quality, artificial groundwater recharge, Mitidja, North Algeria

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Authors: K. Myška, L. Pilařová

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The article deals with possibilities of using cheap mobile devices with the combination of free or open source software tools as an alternative to professional hardware and software equipment. Especially in social work, it is important to find cheap yet functional solution that can compete with complex but expensive solutions for digitizing paper materials. Our research was focused on the analysis of cheap and affordable solutions for digitizing the most frequently used paper materials that are being commonly used by terrain workers in social work. We used comparative analysis as a research method. Social workers need to process data from paper forms quite often. It is still more affordable, time and cost-effective to use paper forms to get feedback in many cases. Collecting data from paper quizzes and questionnaires can be done with the help of professional scanners and software. These technologies are very powerful and have advanced options for digitizing and processing digitized data, but are also very expensive. According to results of our study, the combination of open source software and mobile phone or cheap scanner can be considered as a cost-effective alternative to professional equipment.

Keywords: digitalization, e-learning, mobile devices, questionnaire

Procedia PDF Downloads 150

Authors: Sindhu S Nair, Atul Thakur, Preeti Thakur, Trukhanov Alex

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Perovskite-based absorbing materials that are organic, inorganic, or hybrid have gained interest as an appealing candidate for the development of solar cell devices. Lead-based perovskites are among the most promising materials, but their application is plagued with toxicity and stability concerns. Most of the perovskite solar cell consists of conventional (n-i-p) structure with organic or inorganic charge transport materials. The commercial application of such device is limited due to higher J-V hysteresis and the need for high temperature during fabrication. This numerical analysis primarily directs to investigate the performance of various inorganic lead-free valency ordered double perovskite absorber materials and to develop an inverted perovskite solar cell device structure. Simulation efforts using SCAPS-1D was carried out with various organic and inorganic charge transport materials with absorber layer materials, and their performance has been evaluated for various factors of thickness, absorber thickness, absorber defect density, and interface defect density to achieve the optimized structure.

Keywords: perovskite materials, solar cell, inverted solar cell, inorganic perovskite solar cell materials, cell efficiency

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Authors: Hao Li, Guy Y. Cornejo Maceda, Yiqing Li, Jianguo Tan, Marek Morzynski, Bernd R. Noack

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We propose an automated analysis of the flow control behaviour from an ensemble of control laws and associated time-resolved flow snapshots. The input may be the rich database of machine learning control (MLC) optimizing a feedback law for a cost function in the plant. The proposed methodology provides (1) insights into the control landscape, which maps control laws to performance, including extrema and ridge-lines, (2) a catalogue of representative flow states and their contribution to cost function for investigated control laws and (3) visualization of the dynamics. Key enablers are classification and feature extraction methods of machine learning. The analysis is successfully applied to the stabilization of a mixing layer with sensor-based feedback driving an upstream actuator. The fluctuation energy is reduced by 26%. The control replaces unforced Kelvin-Helmholtz vortices with subsequent vortex pairing by higher-frequency Kelvin-Helmholtz structures of lower energy. These efforts target a human interpretable, fully automated analysis of MLC identifying qualitatively different actuation regimes, distilling corresponding coherent structures, and developing a digital twin of the plant.

Keywords: machine learning control, mixing layer, feedback control, model-free control

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Authors: Emanuel Koseos

Abstract:

Data-Driven Decision Making (DDDM) refers to making decisions that are based on historical data in order to inform practice, develop strategies and implement policies that benefit organizational settings. In educational technology, DDDM facilitates the implementation of differential educational learning approaches such as Educational Data Mining (EDM) and Competency-Based Education (CBE), which commonly target university classrooms. There is a current need for DDDM models applied to middle and secondary schools from a concern for assessing the needs, progress and performance of students and educators with respect to regional standards, policies and evolution of curriculums. To address these concerns, we propose a DDDM reference model developed using educational key process initiatives as inputs to a machine learning framework implemented with statistical software (SAS, R) to provide a best-practices, complex-free and automated approach for educators at their regional level. We assessed the efficiency of the model over a six-year period using data from 45 schools and grades K-12 in the Langley, BC, Canada regional school district. We concluded that the model has wider appeal, such as business learning systems.

Keywords: competency-based learning, data-driven decision making, machine learning, secondary schools

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Authors: Boumesbah Asma, Chergui Mohamed El-amine

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Since it has been shown that the multi-objective minimum spanning tree problem (MOST) is NP-hard even with two criteria, we propose in this study a hybrid NSGA-II algorithm with an exact mutation operator, which is only used with low probability, to find an approximation to the Pareto front of the problem. In a connected graph G, a spanning tree T of G being a connected and cycle-free graph, if k edges of G\T are added to T, we obtain a partial graph H of G inducing a reduced size multi-objective spanning tree problem compared to the initial one. With a weak probability for the mutation operator, an exact method for solving the reduced MOST problem considering the graph H is then used to give birth to several mutated solutions from a spanning tree T. Then, the selection operator of NSGA-II is activated to obtain the Pareto front approximation. Finally, an adaptation of the VNS metaheuristic is called for further improvements on this front. It allows finding good individuals to counterbalance the diversification and the intensification during the optimization search process. Experimental comparison studies with an exact method show promising results and indicate that the proposed algorithm is efficient.

Keywords: minimum spanning tree, multiple objective linear optimization, combinatorial optimization, non-sorting genetic algorithm, variable neighborhood search

Procedia PDF Downloads 88