Search results for: shock-boundary layer interaction
Commenced in January 2007
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Edition: International
Paper Count: 6235

Search results for: shock-boundary layer interaction

4315 Polarimetric Study of System Gelatin / Carboxymethylcellulose in the Food Field

Authors: Sihem Bazid, Meriem El Kolli, Aicha Medjahed

Abstract:

Proteins and polysaccharides are the two types of biopolymers most frequently used in the food industry to control the mechanical properties and structural stability and organoleptic properties of the products. The textural and structural properties of these two types of blend polymers depend on their interaction and their ability to form organized structures. From an industrial point of view, a better understanding of mixtures protein / polysaccharide is an important issue since they are already heavily involved in processed food. It is in this context that we have chosen to work on a model system composed of a fibrous protein mixture (gelatin)/anionic polysaccharide (sodium carboxymethylcellulose). Gelatin, one of the most popular biopolymers, is widely used in food, pharmaceutical, cosmetic and photographic applications, because of its unique functional and technological properties. Sodium Carboxymethylcellulose (NaCMC) is an anionic linear polysaccharide derived from cellulose. It is an important industrial polymer with a wide range of applications. The functional properties of this anionic polysaccharide can be modified by the presence of proteins with which it might interact. Another factor may also manage the interaction of protein-polysaccharide mixtures is the triple helix of the gelatin. Its complex synthesis method results in an extracellular assembly containing several levels. Collagen can be in a soluble state or associate into fibrils, which can associate in fiber. Each level corresponds to an organization recognized by the cellular and metabolic system. Gelatin allows this approach, the formation of gelatin gel has triple helical folding of denatured collagen chains, this gel has been the subject of numerous studies, and it is now known that the properties depend only on the rate of triple helices forming the network. Chemical modification of this system is quite controlled. Observe the dynamics of the triple helix may be relevant in understanding the interactions involved in protein-polysaccharides mixtures. Gelatin is central to any industrial process, understand and analyze the molecular dynamics induced by the triple helix in the transitions gelatin, can have great economic importance in all fields and especially the food. The goal is to understand the possible mechanisms involved depending on the nature of the mixtures obtained. From a fundamental point of view, it is clear that the protective effect of NaCMC on gelatin and conformational changes of the α helix are strongly influenced by the nature of the medium. Our goal is to minimize the maximum the α helix structure changes to maintain more stable gelatin and protect against denaturation that occurs during such conversion processes in the food industry. In order to study the nature of interactions and assess the properties of mixtures, polarimetry was used to monitor the optical parameters and to assess the rate of helicity gelatin.

Keywords: gelatin, sodium carboxymethylcellulose, interaction gelatin-NaCMC, the rate of helicity, polarimetry

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4314 Free Energy Computation of A G-Quadruplex-Ligand Structure: A Classical Molecular Dynamics and Metadynamics Simulation Study

Authors: Juan Antonio Mondragon Sanchez, Ruben Santamaria

Abstract:

The DNA G-quadruplex is a four-stranded DNA structure formed by stacked planes of four base paired guanines (G-quartet). Guanine rich DNA sequences appear in many sites of genomic DNA and can potential form G-quadruplexes, such as those occurring at 3'-terminus of the human telomeric DNA. The formation and stabilization of a G-quadruplex by small ligands at the telomeric region can inhibit the telomerase activity. In turn, the ligands can be used to down regulate oncogene expression making G-quadruplex an attractive target for anticancer therapy. Many G-quadruplex ligands have been proposed with a planar core to facilitate the pi–pi stacking and electrostatic interactions with the G-quartets. However, many drug candidates are impossibilitated to discriminate a G-quadruplex from a double helix DNA structure. In this context, it is important to investigate the site topology for the interaction of a G-quadruplex with a ligand. In this work, we determine the free energy surface of a G-quadruplex-ligand to study the binding modes of the G-quadruplex (TG4T) with the daunomycin (DM) drug. The complex TG4T-DM is studied using classical molecular dynamics in combination with metadynamics simulations. The metadynamics simulations permit an enhanced sampling of the conformational space with a modest computational cost and obtain free energy surfaces in terms of the collective variables (CV). The free energy surfaces of TG4T-DM exhibit other local minima, indicating the presence of additional binding modes of daunomycin that are not observed in short MD simulations without the metadynamics approach. The results are compared with similar calculations on a different structure (the mutated mu-G4T-DM where the 5' thymines on TG4T-DM have been deleted). The results should be of help to design new G-quadruplex drugs, and understand the differences in the recognition topology sites of the duplex and quadruplex DNA structures in their interaction with ligands.

Keywords: g-quadruplex, cancer, molecular dynamics, metadynamics

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4313 Destined Failure of Interactions between Israeli-Arabs and Jews - An Analysis of Creative Works’ Presentation of Issues from the Israeli Side

Authors: Tianqi Yin

Abstract:

Following the establishment of the state of Israel, how to harmonize the relationship between Palestinians and Jews in Israel has always been an intractable problem. As the number of Palestinian Arabs in Israel has increased to over two million, the issue has become more severe. Due to a variety of factors, Israeli Palestinians and Israeli Jews often find it hard to interact with each other, let alone form a relationship. Multiple authors and directors have produced cultural works to touch on the issue, exposing the reasons for the irreconcilable relation between the two ethnic groups. This paper analyzes the representation scenes of the Palestinian-Jewish relationship in three prominent cultural works, each from a distinct perspective, to examine the intrinsic challenges from the Israeli side that curb the two ethnicities from interacting successfully. The first scene is from the Jewish perspective in Amos Oz’s memoir A Tale of Love and Darkness, in which young Oz, a Jewish boy, attempts to interact with Aisha, a young Israeli-Arab girl, but eventually failed because of an accident. The second scene is from a short Israeli film Bus Station which, from an outsider perspective, depicted a brief encounter between an Arab woman and a Jewish woman in Jerusalem. The third scene is the initially successful yet eventually failed relationship between Eyad, a Palestinian boy, and Naomi, a Jewish girl, in an elite Israeli high school from the 2014 film A Borrowed Identity, which is depicted through Eyad’s Arab perspective. Through the analysis of these three narratives, this paper argues that the burden of national responsibility, family influences, and Israeli government’s discriminatory policies are the three main factors on the Jewish side, in ascender order of importance, that make Arab-Jewish interaction hard in Israel.

Keywords: arab-Jewish interaction, ethnographic conflicts, israel, Jewish narrative, narrative styles

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4312 Precursors Signatures of Few Major Earthquakes in Italy Using Very Low Frequency Signal of 45.9kHz

Authors: Keshav Prasad Kandel, Balaram Khadka, Karan Bhatta, Basu Dev Ghimire

Abstract:

Earthquakes still exist as a threating disaster. Being able to predict earthquakes will certainly help prevent substantial loss of life and property. Perhaps, Very Low Frequency/Low Frequency (VLF/LF) signal band (3-30 kHz), which is effectively reflected from D-layer of ionosphere, can be established as a tool to predict earthquake. On May 20 and May 29, 2012, earthquakes of magnitude 6.1 and 5.8 respectively struck Emilia-Romagna of Italy. A year back, on August 24, 2016, an earthquake of magnitude 6.2 struck Central Italy (42.7060 N and 13.2230 E) at 1:36 UT. We present the results obtained from the US Navy VLF Transmitter’s NSY signal of 45.9 kHz transmitted from Niscemi, in the province of Sicily, Italy and received at the Kiel Longwave Monitor, Germany for 2012 and 2016. We analyzed the terminator times, their individual differences and nighttime fluctuation counts. We also analyzed trends, dispersion and nighttime fluctuation which gave us a possible precursors to these earthquakes. Since perturbations in VLF amplitude could also be due to various other factors like lightning, geomagnetic activities (storms, auroras etc.) and solar activities (flares, UV flux, etc.), we filtered the possible perturbations due to these agents to guarantee that the perturbations seen in VLF/LF amplitudes were as a precursor to Earthquakes. As our TRGCP path is North-south, the sunrise and sunset time in transmitter and receiver places matches making pathway for VLF/LF smoother and therefore hoping to obtain more natural data. To our surprise, we found many clear anomalies (as precursors) in terminator times 5 days to 16 days before the earthquakes. Moreover, using night time fluctuation method, we found clear anomalies 5 days to 13 days prior to main earthquakes. This exactly correlates with the findings of previous authors that ionospheric perturbations are seen few days to one month before the seismic activity. In addition to this, we were amazed to observe unexpected decrease of dispersion on certain anomalies where it was supposed to increase, thereby not supporting our finding to some extent. To resolve this problem, we devised a new parameter called dispersion nighttime (dispersion). On analyzing, this parameter decreases significantly on days of nighttime anomalies thereby supporting our precursors to much extent.

Keywords: D-layer, TRGCP (Transmitter Receiver Great Circle Path), terminator times, VLF/LF

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4311 A Multimodal Measurement Approach Using Narratives and Eye Tracking to Investigate Visual Behaviour in Perceiving Naturalistic and Urban Environments

Authors: Khizar Z. Choudhrya, Richard Coles, Salman Qureshi, Robert Ashford, Salim Khan, Rabia R. Mir

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Abstract: The majority of existing landscape research has been derived by conducting heuristic evaluations, without having empirical insight of real participant visual response. In this research, a modern multimodal measurement approach (using narratives and eye tracking) was applied to investigate visual behaviour in perceiving naturalistic and urban environments. This research is unique in exploring gaze behaviour on environmental images possessing different levels of saliency. Eye behaviour is predominantly attracted by salient locations. The concept of methodology of this research on naturalistic and urban environments is drawn from the approaches in market research. Borrowing methodologies from market research that examine visual responses and qualities provided a critical and hitherto unexplored approach. This research has been conducted by using mixed methodological quantitative and qualitative approaches. On the whole, the results of this research corroborated existing landscape research findings, but they also identified potential refinements. The research contributes both methodologically and empirically to human-environment interaction (HEI). This study focused on initial impressions of environmental images with the help of eye tracking. Taking under consideration the importance of the image, this study explored the factors that influence initial fixations in relation to expectations and preferences. In terms of key findings of this research it is noticed that each participant has his own unique navigation style while surfing through different elements of landscape images. This individual navigation style is given the name of ‘visual signature’. This study adds the necessary clarity that would complete the picture and bring an insight for future landscape researchers.

Keywords: human-environment interaction (HEI), multimodal measurement, narratives, eye tracking

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4310 Effect of Oxygen Ion Irradiation on the Structural, Spectral and Optical Properties of L-Arginine Acetate Single Crystals

Authors: N. Renuka, R. Ramesh Babu, N. Vijayan

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Ion beams play a significant role in the process of tuning the properties of materials. Based on the radiation behavior, the engineering materials are categorized into two different types. The first one comprises organic solids which are sensitive to the energy deposited in their electronic system and the second one comprises metals which are insensitive to the energy deposited in their electronic system. However, exposure to swift heavy ions alters this general behavior. Depending on the mass, kinetic energy and nuclear charge, an ion can produce modifications within a thin surface layer or it can penetrate deeply to produce long and narrow distorted area along its path. When a high energetic ion beam impinges on a material, it causes two different types of changes in the material due to the columbic interaction between the target atom and the energetic ion beam: (i) inelastic collisions of the energetic ion with the atomic electrons of the material; and (ii) elastic scattering from the nuclei of the atoms of the material, which is extremely responsible for relocating the atoms of matter from their lattice position. The exposure of the heavy ions renders the material return to equilibrium state during which the material undergoes surface and bulk modifications which depends on the mass of the projectile ion, physical properties of the target material, its energy, and beam dimension. It is well established that electronic stopping power plays a major role in the defect creation mechanism provided it exceeds a threshold which strongly depends on the nature of the target material. There are reports available on heavy ion irradiation especially on crystalline materials to tune their physical and chemical properties. L-Arginine Acetate [LAA] is a potential semi-organic nonlinear optical crystal and its optical, mechanical and thermal properties have already been reported The main objective of the present work is to enhance or tune the structural and optical properties of LAA single crystals by heavy ion irradiation. In the present study, a potential nonlinear optical single crystal, L-arginine acetate (LAA) was grown by slow evaporation solution growth technique. The grown LAA single crystal was irradiated with oxygen ions at the dose rate of 600 krad and 1M rad in order to tune the structural and optical properties. The structural properties of pristine and oxygen ions irradiated LAA single crystals were studied using Powder X- ray diffraction and Fourier Transform Infrared spectral studies which reveal the structural changes that are generated due to irradiation. Optical behavior of pristine and oxygen ions irradiated crystals is studied by UV-Vis-NIR and photoluminescence analyses. From this investigation we can concluded that oxygen ions irradiation modifies the structural and optical properties of LAA single crystals.

Keywords: heavy ion irradiation, NLO single crystal, photoluminescence, X-ray diffractometer

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4309 Biogas Enhancement Using Iron Oxide Nanoparticles and Multi-Wall Carbon Nanotubes

Authors: John Justo Ambuchi, Zhaohan Zhang, Yujie Feng

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Quick development and usage of nanotechnology have resulted to massive use of various nanoparticles, such as iron oxide nanoparticles (IONPs) and multi-wall carbon nanotubes (MWCNTs). Thus, this study investigated the role of IONPs and MWCNTs in enhancing bioenergy recovery. Results show that IONPs at a concentration of 750 mg/L and MWCNTs at a concentration of 1500 mg/L induced faster substrate utilization and biogas production rates than the control. IONPs exhibited higher carbon oxygen demand (COD) removal efficiency than MWCNTs while on the contrary, MWCNT performance on biogas generation was remarkable than IONPs. Furthermore, scanning electron microscopy (SEM) investigation revealed extracellular polymeric substances (EPS) excretion from AGS had an interaction with nanoparticles. This interaction created a protective barrier to microbial consortia hence reducing their cytotoxicity. Microbial community analyses revealed genus predominance of bacteria of Anaerolineaceae and Longilinea. Their role in biodegradation of the substrate could have highly been boosted by nanoparticles. The archaea predominance of the genus level of Methanosaeta and Methanobacterium enhanced methanation process. The presence of bacteria of genus Geobacter was also reported. Their presence might have significantly contributed to direct interspecies electron transfer in the system. Exposure of AGS to nanoparticles promoted direct interspecies electron transfer among the anaerobic fermenting bacteria and their counterpart methanogens during the anaerobic digestion process. This results provide useful insightful information in understanding the response of microorganisms to IONPs and MWCNTs in the complex natural environment.

Keywords: anaerobic granular sludge, extracellular polymeric substances, iron oxide nanoparticles, multi-wall carbon nanotubes

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4308 Variation of Fertility-Related Traits in Italian Tomato Landraces under Mild Heat Stress

Authors: Maurizio E. Picarella, Ludovica Fumelli, Francesca Siligato, Andrea Mazzucato

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Studies on reproductive dynamics in crops subjected to heat stress are crucial to breed more tolerant cultivars. In tomato, cultivars, breeding lines, and wild species have been thoroughly evaluated for the response to heat stress in several studies. Here, we address the reaction to temperature stress in a panel of selected landraces representing genotypes cultivated before the advent of professional varieties that usually show high adaptation to local environments. We adopted an experimental design with two open field trials, where transplanting was spaced by one month. In the second field, plants were thus subjected to mild stress with natural temperature fluctuations. The genotypes showed wide variation for both vegetative (plant height) and reproductive (stigma exsertion, pollen viability, number of flowers per inflorescence, and fruit set) traits. On average, all traits were affected by heat conditions; except for the number of flowers per inflorescence, the “G*E” interaction was always significant. In agreement with studies based on different materials, estimated broad sense heritability was high for plant height, stigma exsertion, and pollen viability and low for the number of flowers per inflorescence and fruit set. Despite the interaction, traits recorded in control and in heat conditions were positively correlated. The first two principal components estimated by multivariate analysis explained more than 50% of the total variability. The study indicated that landraces present a wide variability for the response of reproductive traits to temperature stress and that such variability could be very informative to dissect the traits with higher heritability and identify new QTL useful for breeding more resilient varieties.

Keywords: fruit set, heat stress, solanum lycopersicum L., style exsertion, tomato

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4307 The Effect of PETTLEP Imagery on Equestrian Jumping Tasks

Authors: Nurwina Anuar, Aswad Anuar

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Imagery is a popular mental technique used by athletes and coaches to improve learning and performance. It has been widely investigated and beneficial in the sports context. However, the imagery application in equestrian sport has been understudied. Thus, the effectiveness of imagery should encompass the application in the equestrian sport to ensure its application covert all sports. Unlike most sports (e.g., football, badminton, tennis, ski) which are both mental and physical are dependent solely upon human decision and response, equestrian sports involves the interaction of human-horse collaboration to success in the equestrian tasks. This study aims to investigate the effect of PETTLEP imagery on equestrian jumping tasks, motivation and imagery ability. It was hypothesized that the use of PETTLEP imagery intervention will significantly increase in the skill equestrian jumping tasks. It was also hypothesized that riders’ imagery ability and motivation will increase across phases. The participants were skilled riders with less to no imagery experience. A single-subject ABA design was employed. The study was occurred over five week’s period at Universiti Teknologi Malaysia Equestrian Park. Imagery ability was measured using the Sport Imagery Assessment Questionnaires (SIAQ), the motivational measured based on the Motivational imagery ability measure for Sport (MIAMS). The effectiveness of the PETTLEP imagery intervention on show jumping tasks were evaluated by the professional equine rider on the observational scale. Results demonstrated the improvement on all equestrian jumping tasks for the most participants from baseline to intervention. Result shows the improvement on imagery ability and participants’ motivations after the PETTLEP imagery intervention. Implication of the present study include underlining the impact of PETTLEP imagery on equestrian jumping tasks. The result extends the previous research on the effectiveness of PETTLEP imagery in the sports context that involves interaction and collaboration between human and horse.

Keywords: PETTLEP imagery, imagery ability, equestrian, equestrian jumping tasks

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4306 Soret-Driven Convection in a Binary Fluid with Coriolis Force

Authors: N. H. Z. Abidin, N. F. M. Mokhtar, S. S. A. Gani

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The influence of diffusion of the thermal or known as Soret effect in a heated Binary fluid model with Coriolis force is investigated theoretically. The linear stability analysis is used, and the eigenvalue is obtained using the Galerkin method. The impact of the Soret and Coriolis force on the onset of stationary convection in a system is analysed with respect to various Binary fluid parameters and presented graphically. It is found that an increase of the Soret values, destabilize the Binary fluid layer system. However, elevating the values of the Coriolis force helps to lag the onset of convection in a system.

Keywords: Benard convection, binary fluid, Coriolis, Soret

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4305 Free-Standing Pd-Based Metallic Glass Membranes for MEMS Applications

Authors: Wei-Shan Wang, Klaus Vogel, Felix Gabler, Maik Wiemer, Thomas Gessner

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Metallic glasses, which are free of grain boundaries, have superior properties including large elastic limits, high strength, and excellent wear and corrosion resistance. Therefore, bulk metallic glasses (BMG) and thin film metallic glasses (TFMG) have been widely developed and investigated. Among various kinds of metallic glasses, Pd-Cu-Si TFMG, which has lower elastic modulus and better resistance of oxidation and corrosions compared to Zr- and Fe-based TFMGs, can be a promising candidate for MEMS applications. However, the study of Pd-TFMG membrane is still limited. This paper presents free-standing Pd-based metallic glass membranes with large area fabricated on wafer level for the first time. Properties of Pd-Cu-Si thin film metallic glass (TFMG) with various deposition parameters are investigated first. When deposited at 25°C, compressive stress occurs in the Pd76Cu6Si18 thin film regardless of Ar pressure. When substrate temperature is increased to 275°C, the stress state changes from compressive to tensile. Thin film stresses are slightly decreased when Ar pressure is higher. To show the influence of temperature on Pd-TFMGs, thin films without and with post annealing below (275°C) and within (370°C) supercooled liquid region are investigated. Results of XRD and TEM analysis indicate that Pd-TFMGs remain amorphous structure with well-controlled parameters. After verification of amorphous structure of the Pd-TFMGs, free-standing Pd-Cu-Si membranes were fabricated by depositing Pd-Cu-Si thin films directly on 200nm-thick silicon nitride membranes, followed by post annealing and dry etching of silicon nitride layer. Post annealing before SiNx removal is used to further release internal stress of Pd-TFMGs. The edge length of the square membrane ranges from 5 to 8mm. The effect of post annealing on Pd-Cu-Si membranes are discussed as well. With annealing at 370°C for 5 min, Pd-MG membranes are fully distortion-free after removal of SiNx layer. Results show that, by introducing annealing process, the stress-relief, distortion-free Pd-TFMG membranes with large area can be a promising candidate for sensing applications such as pressure and gas sensors.

Keywords: amorphous alloy, annealing, metallic glasses, TFMG membrane

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4304 Interaction between the Rio Conventions on Climate and Biodiversity: Analysis of the Integration of Ecosystem-Based Approaches and Nature-Based Solutions into the UNFCCC

Authors: Dieudonne Mevono Mvogo

Abstract:

The Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES)-Intergovernmental Panel on Climate Change (IPCC) co-sponsored workshop report suggests that climate change and biodiversity loss are two of the most pressing issues of the Anthropocene. Research establishes the interconnection between climate change and biodiversity. On the one hand, the impact of climate change on biodiversity loss – 14 % over the past century – is projected to surpass other threats – land and sea use 34 % and direct exploitation of species 23 % – during the 21st century. Response measures to climate change also affect biodiversity negatively or positively. On the other hand, actions to halt or reverse biodiversity loss can enhance land and ocean capacity for carbon sequestration. These actions can also promote adaptation by ensuring adaptive capacity. This systemic interaction between climate change and biodiversity affects the human quality of life. The United Nations Secretariat's report entitled 'Gaps in international environmental law and environment-related instruments: towards a global pact for the environment,' released in 2018, states that cooperation and mutual support among agreements dealing with climate change, the protection of the marine environment, freshwater resources and hazardous waste are indispensable for the effective implementation of the Convention on the Biological Diversity (CBD). Since biodiversity is being lost at an alarming rate, this study aims to evaluate the cooperative framework for the coherence and coordination between climate change and biodiversity regimes to provide co-benefits for climate and biodiversity crises. It questions the potential improvement regarding integrating ecosystem-based approaches and nature-based solutions – promoted by the CBD – into the United Nations Framework Convention on Climate Change (UNFCCC).

Keywords: rio conventions, climate change, biodiversity, cooperative framework, ecosystem-based approaches, nature-based solutions

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4303 Impact of Crime on Women and Their Families in Rural Areas of Haryana State in India

Authors: Rashmi Tyagi, Savita Vermani

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Violence against women is the result of long-standing power imbalance between men and women and thus seriously compromises the well-being, productivity and contribution of one half the population. The costs incurred to the family especially children and society at large in terms of physical, psychological, social and financial losses are huge. The communities’ native to the state of Haryana in India is primarily patriarchal, burdened with age old regressive mindset under the socio-cultural and religious structures which discriminates against women. Therefore it was important to bring to light the issues affecting women in this region. Therefore this study focused on studying the consequences of crime on victim women and their families. Two hundred women were randomly selected and out of those one hundred twenty, who were affected with some kind of violence were interviewed. Data was collected and statistically analyzed for physical, psychological, inter-family and societal consequences of violence on these women. Women reported physical injuries, gynecological problems, unwanted pregnancies, frigidity, phobia and sexual dysfunction. 58.9% women felt decreased work efficiency. Psychological problems encountered were anxiety, isolation, depression, suicidal tendencies. 66.7% respondents suffered from anxiety followed by 65.0% faced depression symptoms. At family levels, 40.0% respondents felt the atmosphere was unsuitable for children while 39.2% reported lack of interaction. The societal consequences reported were breakdown of interaction with friends and family (44.2%) and resulting humiliation and demeaning remarks from others (38.3%). The impact of violence on women had an adverse effect on children. 36.7% children felt responsible for abuse and powerless to stop it, 29.2% reported living with fear. Concerted efforts are required to curb violence against women in Haryana.

Keywords: impact of violence against women on children, patriarchal society, physical psychological and societal consequences, violence against women

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4302 Natural Convection between Two Parallel Wavy Plates

Authors: Si Abdallah Mayouf

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In this work, the effects of the wavy surface on free convection heat transfer boundary layer flow between two parallel wavy plates have been studied numerically. The two plates are considered at a constant temperature. The equations and the boundary conditions are discretized by the finite difference scheme and solved numerically using the Gauss-Seidel algorithm. The important parameters in this problem are the amplitude of the wavy surfaces and the distance between the two wavy plates. Results are presented as velocity profiles, temperature profiles and local Nusselt number according to the important parameters.

Keywords: free convection, wavy surface, parallel plates, fluid dynamics

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4301 Structure-Phase States of Al-Si Alloy After Electron-Beam Treatment and Multicycle Fatigue

Authors: Krestina V. Alsaraeva, Victor E. Gromov, Sergey V. Konovalov, Anna A. Atroshkina

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Processing of Al-19.4Si alloy by high intensive electron beam has been carried out and multiple increase in fatigue life of the material has been revealed. Investigations of structure and surface modified layer destruction of Al-19.4Si alloy subjected to multicycle fatigue tests to fracture have been carried out by methods of scanning electron microscopy. The factors responsible for the increase of fatigue life of Al-19.4Si alloy have been revealed and analyzed.

Keywords: Al-19.4Si alloy, high intensive electron beam, multicycle fatigue, structure

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4300 The Impact of Selected Personality Skills on Intercultural Interaction and Communication of Students of Social Pedagogy in the Czech Republic

Authors: Irena Balaban Cakirpaloglu, Karla Hrbackova

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This paper focuses on the issue of intercultural competencies of university students who are preparing to work in assisting professions. In recent years, the Czech Republic has become a major destination for many people from different cultural environments, and there is a growing need for workers in assisting professions to be able to respond flexibly and adequately to the changing living conditions of multicultural coexistence. The main objective of this study is to analyse the preparedness of students in assisting professions in relation to intercultural competencies. Intercultural competences include several essential skills for working successfully with diversity. Taking into account the main objective of this research, a pilot study was conducted among students of Social Pedagogy at the Faculty of Humanities at Tomas Bata University in Zlin in the academic year 2017/2018. The research sample consisted of 116 students. To obtain the data, we used the Cross-Cultural Adaptability Inventory (CCAI) by Kelley and Meyers. The inventory maps strengths and weaknesses in 4 skill areas: Emotional Resilience, Flexibility/Openness, Perceptual Acuity and Personal Autonomy. This inventory also examines individual ability to succeed in intercultural interaction and communication. The results obtained from the survey were statistically processed and analysed using the relevant statistical methods. The results of the survey point to the fact that students of social pedagogy achieve average to below average results in individual skill areas. At the same time, significant differences have been detected among the students with work experience in multicultural environment and those with no experience.

Keywords: cross–cultural adaptability inventory, diversity, intercultural competences, students of social pedagogy

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4299 Improvement of the Quality Services of Social Robots by Understanding Requirements of People with Dementia

Authors: Konrad Rejdak, Agnieszka Korchut, Sebastian Szklener, Urszula Skrobas, Justyna Gerlowska, Katarzyna Grabowska-Aleksandrowicz, Dorota Szczesniak-Stanczyk

Abstract:

Introduction: Neurodegenerative diseases are frequently accompanied by loss and unwanted change in functional independence, social relationships, and economic circumstances. Currently, the achievements of social robots to date is being projected to improve multidimensional quality of life among people with cognitive impairment and others. Objectives: Identification of particular human needs in context of the changes occurring in course of neurodegenerative diseases. Methods: Based on the 110 surveys performed in Medical University of Lublin from medical staff, patients, and caregivers we made prioritization of the users' needs as: high, medium, and low. The issues included in the surveys concerned four aspects: user acceptance, functional requirements, design of the robotic assistant and preferred types of human-robot interaction. Results: We received completed questionnaires: 50 from medical staff, 30 from caregivers and 30 from potential users. Above 90% of the respondents from each of the three groups, accepted robotic assistant as a potential caregiver. High priority functional capability of assistive technology was to handle emergencies in a private home like recognizing life-threatening situations and reminding about medication intake. With reference to design of the robotic assistant, the majority of the respondent would like to have an anthropomorphic appearance with positive emotionally expressive face. The most important type of human-robot interaction was voice-operated system and by touchscreen. Conclusion: The results from our study might contribute to a better understanding of the system and users’ requirements for the development of a service robot intended to support patients with dementia.

Keywords: social robot, dementia, requirements, patients needs

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4298 Performance Improvement of UWB Corrugated Antipodal Vivaldi Antenna Using Spiral Shape Negative Index Metamaterial

Authors: Rahul Singha, D. Vakula

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This paper presents a corrugated antipodal vivaldi antenna with improved performance by using negative index metamaterial (NIM) of the Archimedean spiral design. A single layer NIM piece is placed perpendicular middle of the two arm of the proposed antenna. The antenna size is 30×60×0.787 mm3 operating at 8GHz. The simulated results of NIM corrugated antipodal vivaldi antenna show that the gain and directivity has increased up to 1.2dB and 1dB respectively. The HPBW is increased by 90 with the reflection coefficient less than ‒10 dB from 4.7 GHz to 11 GHz for UWB application.

Keywords: Negative Index Metamaterial (NIM), Ultra Wide Band (UWB), Half Power Beam Width (HPBW), vivaldi antenna

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4297 Fully Eulerian Finite Element Methodology for the Numerical Modeling of the Dynamics of Heart Valves

Authors: Aymen Laadhari

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During the last decade, an increasing number of contributions have been made in the fields of scientific computing and numerical methodologies applied to the study of the hemodynamics in the heart. In contrast, the numerical aspects concerning the interaction of pulsatile blood flow with highly deformable thin leaflets have been much less explored. This coupled problem remains extremely challenging and numerical difficulties include e.g. the resolution of full Fluid-Structure Interaction problem with large deformations of extremely thin leaflets, substantial mesh deformations, high transvalvular pressure discontinuities, contact between leaflets. Although the Lagrangian description of the structural motion and strain measures is naturally used, many numerical complexities can arise when studying large deformations of thin structures. Eulerian approaches represent a promising alternative to readily model large deformations and handle contact issues. We present a fully Eulerian finite element methodology tailored for the simulation of pulsatile blood flow in the aorta and sinus of Valsalva interacting with highly deformable thin leaflets. Our method enables to use a fluid solver on a fixed mesh, whilst being able to easily model the mechanical properties of the valve. We introduce a semi-implicit time integration scheme based on a consistent NewtonRaphson linearization. A variant of the classical Newton method is introduced and guarantees a third-order convergence. High-fidelity computational geometries are built and simulations are performed under physiological conditions. We address in detail the main features of the proposed method, and we report several experiments with the aim of illustrating its accuracy and efficiency.

Keywords: eulerian, level set, newton, valve

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4296 Size Distribution Effect of InAs/InP Self–Organized Quantum Dots on Optical Properties

Authors: Abdelkader Nouri, M’hamed Bouslama, Faouzi Saidi, Hassan Maaref, Michel Gendry

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Self-organized InAs quantum dots (QDs) have been grown on 3,1% InP (110) lattice mismatched substrate by Solid Source Molecular Beam Epitaxy (SSMBE). Stranski-Krastanov mode growth has been used to create self-assembled 3D islands on InAs wetting layer (WL). The optical quality depending on the temperature and power is evaluated. In addition, Atomic Force Microscopy (AFM) images shows inhomogeneous island dots size distribution due to temperature coalescence. The quantum size effect was clearly observed through the spectra photoluminescence (PL) shape.

Keywords: AFM, InAs QDs, PL, SSMBE

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4295 Metal-Based Deep Eutectic Solvents for Extractive Desulfurization of Fuels: Analysis from Molecular Dynamics Simulations

Authors: Aibek Kukpayev, Dhawal Shah

Abstract:

Combustion of sour fuels containing high amount of sulfur leads to the formation of sulfur oxides, which adversely harm the environment and has a negative impact on human health. Considering this, several legislations have been imposed to bring down the sulfur content in fuel to less than 10 ppm. In recent years, novel deep eutectic solvents (DESs) have been developed to achieve deep desulfurization, particularly to extract thiophenic compounds from liquid fuels. These novel DESs, considered as analogous to ionic liquids are green, eco-friendly, inexpensive, and sustainable. We herein, using molecular dynamic simulation, analyze the interactions of metal-based DESs with model oil consisting of thiophenic compounds. The DES used consists of polyethylene glycol (PEG-200) as a hydrogen bond donor, choline chloride (ChCl) or tetrabutyl ammonium chloride (TBAC) as a hydrogen bond acceptor, and cobalt chloride (CoCl₂) as metal salt. In particular, the combination of ChCl: PEG-200:CoCl₂ at a ratio 1:2:1 and the combination of TBAC:PEG-200:CoCl₂ at a ratio 1:2:0.25 were simulated, separately, with model oil consisting of octane and thiophenes at 25ᵒC and 1 bar. The results of molecular dynamics simulations were analyzed in terms of interaction energies between different components. The simulations revealed a stronger interaction between DESs/thiophenes as compared with octane/thiophenes, suggestive of an efficient desulfurization process. In addition, our analysis suggests that the choice of hydrogen bond acceptor strongly influences the efficiency of the desulfurization process. Taken together, the results also show the importance of the metal ion, although present in small amount, in the process, and the role of the polymer in desulfurization of the model fuel.

Keywords: deep eutectic solvents, desulfurization, molecular dynamics simulations, thiophenes

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4294 Fresh Amnion Membrane Grafting for the Regeneration of Skin in Full Thickness Burn in Newborn - Case Report

Authors: Priyanka Yadav, Umesh Bnasal, Yashvinder Kumar

Abstract:

The placenta is an important structure that provides oxygen and nutrients to the growing fetus in utero. It is usually thrown away after birth, but it has a therapeutic role in the regeneration of tissue. It is covered by the amniotic membrane, which can be easily separated into the amnion layer and the chorion layer—the amnion layer act as a biofilm for the healing of burn wound and non-healing ulcers. The freshly collected membrane has stem cells, cytokines, growth factors, and anti-inflammatory properties, which act as a biofilm for the healing of wounds. It functions as a barrier and prevents heat and water loss and also protects from bacterial contamination, thus supporting the healing process. The application of Amnion membranes has been successfully used for wound and reconstructive purposes for decades. It is a very cheap and easy process and has shown superior results to allograft and xenograft. However, there are very few case reports of amnion membrane grafting in newborns; we intend to highlight its therapeutic importance in burn injuries in newborns. We present a case of 9 days old male neonate who presented to the neonatal unit of Maulana Azad Medical College with a complaint of fluid-filled blisters and burns wound on the body for six days. He was born outside the hospital at 38 weeks of gestation to a 24-year-old primigravida mother by vaginal delivery. The presentation was cephalic and the amniotic fluid was clear. His birth weight was 2800 gm and APGAR scores were 7 and 8 at 1 and 5 minutes, respectively. His anthropometry was appropriate for gestational age. He developed respiratory distress after birth requiring oxygen support by nasal prongs for three days. On the day of life three, he developed blisters on his body, starting from than face then over the back and perineal region. At a presentation on the day of life nine, he had blisters and necrotic wound on the right side of the face, back, right shoulder and genitalia, affecting 60% of body surface area with full-thickness loss of skin. He was started on intravenous antibiotics and fluid therapy. Pus culture grew Pseudomonas aeuroginosa, for which culture-specific antibiotics were started. Plastic surgery reference was taken and regular wound dressing was done with antiseptics. He had a storming course during the hospital stay. On the day of life 35 when the baby was hemodynamically stable, amnion membrane grafting was done on the wound site; for the grafting, fresh amnion membrane was removed under sterile conditions from the placenta obtained by caesarean section. It was then transported to the plastic surgery unit in half an hour in a sterile fluid where the graft was applied over the infant’s wound. The amnion membrane grafting was done twice in two weeks for covering the whole wound area. After successful uptake of amnion membrane, skin from the thigh region was autografted over the whole wound area by Meek technique in a single setting. The uptake of autograft was excellent and most of the areas were healed. In some areas, there was patchy regeneration of skin so dressing was continued. The infant was discharged after three months of hospital stay and was later followed up in the plastic surgery unit of the hospital.

Keywords: amnion membrane grafting, autograft, meek technique, newborn, regeneration of skin

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4293 Building and Development of the Stock Market Institutional Infrastructure in Russia

Authors: Irina Bondarenko, Olga Vandina

Abstract:

The theory of evolutionary economics is the basis for preparation and application of methods forming the stock market infrastructure development concept. The authors believe that the basis for the process of formation and development of the stock market model infrastructure in Russia is the theory of large systems. This theory considers the financial market infrastructure as a whole on the basis of macroeconomic approach with the further definition of its aims and objectives. Evaluation of the prospects for interaction of securities market institutions will enable identifying the problems associated with the development of this system. The interaction of elements of the stock market infrastructure allows to reduce the costs and time of transactions, thereby freeing up resources of market participants for more efficient operation. Thus, methodology of the transaction analysis allows to determine the financial infrastructure as a set of specialized institutions that form a modern quasi-stable system. The financial infrastructure, based on international standards, should include trading systems, regulatory and supervisory bodies, rating agencies, settlement, clearing and depository organizations. Distribution of financial assets, reducing the magnitude of transaction costs, increased transparency of the market are promising tasks in the solution for questions of services level and quality increase provided by institutions of the securities market financial infrastructure. In order to improve the efficiency of the regulatory system, it is necessary to provide "standards" for all market participants. The development of a clear regulation for the barrier to the stock market entry and exit, provision of conditions for the development and implementation of new laws regulating the activities of participants in the securities market, as well as formulation of proposals aimed at minimizing risks and costs, will enable the achievement of positive results. The latter will be manifested in increasing the level of market participant security and, accordingly, the attractiveness of this market for investors and issuers.

Keywords: institutional infrastructure, financial assets, regulatory system, stock market, transparency of the market

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4292 Virtual Reference Service as a Space for Communication and Interaction: Providing Infrastructure for Learning in Times of Crisis at Uppsala University

Authors: Nadja Ylvestedt

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Uppsala University Library is a geographically dispersed research library consisting of nine subject libraries located in different campus areas throughout the city of Uppsala. Despite the geographical dispersion, it is the library's ambition to be perceived as a cohesive library with consistently high service and quality. A key factor to being one cohesive library is the library's online services, especially the virtual reference service. E-mail, chat and phone are answered by a team of specially trained staff under the supervision of a team leader. When covid-19 hit, well-established routines and processes to provide an infrastructure for students and researchers at the university changed radically. The strong connection between services provided at the library locations as well as at the VRS has been one of the key components of the library’s success in providing patrons with the help they need. With radically minimized availability at the physical locations, the infrastructure was at risk of collapsing. Objectives:- The objective of this project has been to evaluate the consequences of the sudden change in the organization of the library. The focus of this evaluation is the library’s VRS as an important space for learning, interaction and communication between the library and the community when other traditional spaces were not available. The goal of this evaluation is to capture the lessons learned from providing infrastructure for learning and research in times of crisis both on a practical, user-centered level but also to stress the importance of leadership in ever-changing environments that supports and creates agile, flexible services and teams instead of rigid processes adhering to obsolete goals. Results:- Reduced availability at the physical library locations was one of the strategies to prevent the spread of the covid-19 virus. The library staff was encouraged to work from home, so student workers staffed the library’s physical locations during that time, leaving the VRS to be the only place where patrons could get expert help. The VRS had an increase of 65% of questions asked between spring term 2019 and spring term 2020. The VRS team had to navigate often complicated and fast-changing new routines depending on national guidelines. The VRS team has a strong emphasis on agility in their approach to the challenges and opportunities, with methods to evaluate decisions regularly with user experience in mind. Fast decision-making, collecting feedback, an open-minded approach to reviewing rules and processes with both a short-term and a long-term focus and providing a healthy work environment have been key factors in managing this crisis and learn from it. This was resting on a strong sense of ownership regarding the VRS, well-working communication tools and agile and active communication between team members, as well as between the team and the rest of the organization who served as a second-line support system to aid the VRS team. Moving forward, the VRS has become an important space for communication, interaction and provider of infrastructure, implementing new routines and more extensive availability due to the lessons learned during crisis. The evaluation shows that the virtual environment has become an important addition to the physical spaces, existing in its own right but always in connection with and in relationship with the library structure as a whole. Thereby showing that the basis of human interaction stays the same while its form morphs and adapts to changes, thus leaving the virtual environment as a space of communication and infrastructure with unique opportunities for outreach and the potential to become a staple in patron’s education and learning.

Keywords: virtual reference service, leadership, digital infrastructure, research library

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4291 Unsupervised Classification of DNA Barcodes Species Using Multi-Library Wavelet Networks

Authors: Abdesselem Dakhli, Wajdi Bellil, Chokri Ben Amar

Abstract:

DNA Barcode, a short mitochondrial DNA fragment, made up of three subunits; a phosphate group, sugar and nucleic bases (A, T, C, and G). They provide good sources of information needed to classify living species. Such intuition has been confirmed by many experimental results. Species classification with DNA Barcode sequences has been studied by several researchers. The classification problem assigns unknown species to known ones by analyzing their Barcode. This task has to be supported with reliable methods and algorithms. To analyze species regions or entire genomes, it becomes necessary to use similarity sequence methods. A large set of sequences can be simultaneously compared using Multiple Sequence Alignment which is known to be NP-complete. To make this type of analysis feasible, heuristics, like progressive alignment, have been developed. Another tool for similarity search against a database of sequences is BLAST, which outputs shorter regions of high similarity between a query sequence and matched sequences in the database. However, all these methods are still computationally very expensive and require significant computational infrastructure. Our goal is to build predictive models that are highly accurate and interpretable. This method permits to avoid the complex problem of form and structure in different classes of organisms. On empirical data and their classification performances are compared with other methods. Our system consists of three phases. The first is called transformation, which is composed of three steps; Electron-Ion Interaction Pseudopotential (EIIP) for the codification of DNA Barcodes, Fourier Transform and Power Spectrum Signal Processing. The second is called approximation, which is empowered by the use of Multi Llibrary Wavelet Neural Networks (MLWNN).The third is called the classification of DNA Barcodes, which is realized by applying the algorithm of hierarchical classification.

Keywords: DNA barcode, electron-ion interaction pseudopotential, Multi Library Wavelet Neural Networks (MLWNN)

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4290 Different Views and Evaluations of IT Artifacts

Authors: Sameh Al-Natour, Izak Benbasat

Abstract:

The introduction of a multitude of new and interactive e-commerce information technology (IT) artifacts has impacted adoption research. Rather than solely functioning as productivity tools, new IT artifacts assume the roles of interaction mediators and social actors. This paper describes the varying roles assumed by IT artifacts, and proposes and distinguishes between four distinct foci of how the artifacts are evaluated. It further proposes a theoretical model that maps the different views of IT artifacts to four distinct types of evaluations.

Keywords: IT adoption, IT artifacts, similarity, social actor

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4289 Effect of Adverse Pressure Gradient on a Fluctuating Velocity over the Co-Flow Jet Airfoil

Authors: Morteza Mirhosseini, Amir B. Khoshnevis

Abstract:

The boundary layer separation and new active flow control of a NACA 0025 airfoil were studied experimentally. This new flow control is sometimes known as a co-flow jet (cfj) airfoil. This paper presents the fluctuating velocity in a wall jet over the co-flow jet airfoil subjected to an adverse pressure gradient and a curved surface. In these results, the fluctuating velocity at the inner part increasing by increased the angle of attack up to 12o and this has due to the jet energized, while the angle of attack 20o has different. The airfoil cord based Reynolds number has 105.

Keywords: adverse pressure gradient, fluctuating velocity, wall jet, co-flow jet airfoil

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4288 Values in Higher Education: A Case Study of Higher Education Students

Authors: Bahadır Erişti

Abstract:

Values are the behavioral procedures of society based communication and interaction process that includes social and cultural backgrounds. The policy of learning and teaching in higher education is oriented towards constructing knowledge and skills, based on theorist framework of cognitive and psychomotor aspects. This approach makes people not to develop generosity, empathy, affection, solidarity, justice, equality and so on. But the sensorial gains of education system provide the integrity of society interaction. This situation carries out the necessity of values education’s in higher education. The current study aims to consider values education from the viewpoint of students in higher education. Within the framework of the current study, an open ended survey based scenario of higher education students was conducted with the students’ social, cognitive, affective and moral developments. In line with this purpose, the following situations of the higher education system were addressed based on the higher education students’ viewpoint: The views of higher education students’ regarding values that are tried to be gained at the higher education system; The higher education students’ suggestions regarding values education at the higher education system; The views of the higher education students’ regarding values that are imposed at the higher education system. In this study, descriptive qualitative research method was used. The study group of the research is composed of 20 higher education postgraduate students at Curriculum and Instruction Department of Educational Sciences at Anadolu University. An open-ended survey was applied for the purpose of collecting qualitative data. As a result of the study, value preferences, value judgments and value systems of the higher education students were constructed on prioritizes based on social, cultural and economic backgrounds and statues. Multi-dimensional process of value education in higher education need to be constructed on higher education-community-cultural background cooperation. Thus, the act of judgement upon values between higher education students based on the survey seems to be inherent in the system of education itself. The present study highlights the students’ value priorities and importance of values in higher education. If the purpose of the higher education system gains on values, it is possible to enable society to promote humanity.

Keywords: higher education, value, values education, values in higher education

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4287 Tensile and Direct Shear Responses of Basalt-Fibre Reinforced Composite Using Alkali Activate Binder

Authors: S. Candamano, A. Iorfida, L. Pagnotta, F. Crea

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Basalt fabric reinforced cementitious composites (FRCM) have attracted great attention because they result in being effective in structural strengthening and eco-efficient. In this study, authors investigate their mechanical behavior when an alkali-activated binder, with tuned properties and containing high amounts of industrial by-products, such as ground granulated blast furnace slag, is used. Reinforcement is made up of a balanced, coated bidirectional fabric made out of basalt fibres and stainless steel micro-wire, with a mesh size of 8x8 mm and an equivalent design thickness equal to 0.064 mm. Mortars mixes have been prepared by maintaining constant the water/(reactive powders) and sand/(reactive powders) ratios at 0.53 and 2.7 respectively. Tensile tests were carried out on composite specimens of nominal dimensions equal to 500 mm x 50 mm x 10 mm, with 6 embedded rovings in the loading direction. Direct shear tests (DST), aimed to the stress-transfer mechanism and failure modes of basalt-FRCM composites, were carried out on brickwork substrate using an externally bonded basalt-FRCM composite strip 10 mm thick, 50 mm wide and a bonded length of 300 mm. Mortars exhibit, after 28 days of curing, a compressive strength of 32 MPa and a flexural strength of 5.5 MPa. Main hydration product is a poorly crystalline CASH gel. The constitutive behavior of the composite has been identified by means of direct tensile tests, with response curves showing a tri-linear behavior. The first linear phase represents the uncracked (I) stage, the second (II) is identified by crack development and the third (III) corresponds to cracked stage, completely developed up to failure. All specimens exhibit a crack pattern throughout the gauge length and failure occurred as a result of sequential tensile failure of the fibre bundles, after reaching the ultimate tensile strength. The behavior is mainly governed by cracks development (II) and widening (III) up to failure. The main average values related to the stages are σI= 173 MPa and εI= 0.026% that are the stress and strain of the transition point between stages I and II, corresponding to the first mortar cracking; σu = 456 MPa and εu= 2.20% that are the ultimate tensile strength and strain, respectively. The tensile modulus of elasticity in stage III is EIII= 41 GPa. All single-lap shear test specimens failed due to composite debonding. It occurred at the internal fabric-to-matrix interface, and it was the result of fracture of the matrix between the fibre bundles. For all specimens, transversal cracks were visible on the external surface of the composite and involved only the external matrix layer. This cracking appears when the interfacial shear stresses increase and slippage of the fabric at the internal matrix layer interface occurs. Since the external matrix layer is bonded to the reinforcement fabric, it translates with the slipped fabric. Average peak load around 945 N, peak stress around 308 MPa, and global slip around 6 mm were measured. The preliminary test results allow affirming that Alkali Activated Binders can be considered a potentially valid alternative to traditional mortars in designing FRCM composites.

Keywords: alkali activated binders, basalt-FRCM composites, direct shear tests, structural strengthening

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4286 Constructed Wetlands with Subsurface Flow for Nitrogen and Metazachlor Removal from Tile Drainage: First Year Results

Authors: P. Fucik, J. Vymazal, M. Seres

Abstract:

Pollution from agricultural drainage is a severe issue for water quality, and it is a major reason for the failure in accomplishment of 'good chemical status' according to Water Framework Directive, especially due to high nitrogen and pesticide burden of receiving waters. Constructed wetlands were proposed as a suitable measure for removal of nitrogen from agricultural drainage in the early 1990s. Until now, the vast majority of constructed wetlands designed to treat tile drainage were free-surface constructed wetlands. In 2018, three small experimental constructed wetlands with horizontal subsurface flow were built in Czech Highlands to treat tile drainage from 15.73 ha watershed. The wetlands have a surface area of 79, 90 and 98 m² and were planted with Phalaris arundinacea and Glyceria maxima in parallel bands. The substrate in the first two wetlands is gravel (4-8 mm) mixed with birch woodchips (10:1 volume ratio). In one of those wetlands, the water level is kept 10 cm above the surface; in the second one, the water is kept below the surface. The third wetland has 20 cm layer of birch woodchips on top of gravel. The drainage outlet, as well as wetland outlets, are equipped with automatic discharge-gauging devices, temperature probes, as well as automatic water samplers (Teledyne ISCO). During the monitored period (2018-2019), the flows were unexpectedly low due to a drop of the shallow ground water level, being the main source of water for the monitored drainage system, as experienced at many areas of the Czech Republic. The mean water residence time was analyzed in the wetlands (KBr), which was 16, 9 and 27 days, respectively. The mean total nitrogen concentration eliminations during one-year period were 61.2%, 62.6%, and 70.9% for wetlands 1, 2, and 3, respectively. The average load removals amounted to 0.516, 0.323, and 0.399 g N m-2 d-1 or 1885, 1180 and 1457 kg ha-1 yr-1 in wetlands 1, 2 and 3, respectively. The plant uptake and nitrogen sequestration in aboveground biomass contributed only marginally to the overall nitrogen removal. Among the three variants, the one with shallow water on the surface was revealed to be the most effective for removal of nitrogen from drainage water. In August 2019, herbicide Metazachlor was experimentally poured in time of 2 hours at drainage outlet in a concentration of 250 ug/l to find out the removal rates of the aforementioned wetlands. Water samples were taken the first day every six hours, and for the next nine days, every day one water sample was taken. The removal rates were as follows 94, 69 and 99%; when the most effective wetland was the one with the longest water residence time and the birch woodchip-layer on top of gravel.

Keywords: constructed wetlands, metazachlor, nitrogen, tile drainage

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