Search results for: high voltage production

Authors: Kai-Wei Huang, Yi-Feng Lin

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The purpose of this study is to have chemical resistance, high heat resistance and mechanical strength of ceramic hollow fiber membrane into a membrane contactor, and the combustion process is applied (Post-combustion capture) of the carbon dioxide absorption device. In this paper, we would investigate the effect of the ceramic membrane hydrophobicity to the flux of the carbon dioxide adsorption. To improve the applicability of the ceramic film. We use the dry-wet spinning method with the high temperature sintering process for preparing a ceramic hollow fiber membranes to increase the filling density per unit volume of the membrane. The PESf/Al2O3 ratio of 1:5 was prepared ceramic hollow fibers membrane precursors and investigate the relationship of the different sintering temperature to the membrane pore size and porosity. It can be found that the membrane via the sintering temperature of 1400 °C prepared with the highest porosity of 70%, while the membrane via the sintering temperature of 1600 °C prepared although has a minimum porosity of about 54%, but also has the smallest average pore size of about 0.2 μm. The hydrophilic ceramic hollow fiber membranes which after high-temperature sintering were changed into hydrophobic successfully via the 0.02M FAS modifier. The hydrophobic ceramic hollow fiber membranes with different sintering temperature, the membrane which was prepared via 1400 °C sintering has the highest carbon dioxide adsorption about 4.2 × 10-4 (mole/m2s). The membrane prepared via 1500 °C sintering has the carbon dioxide adsorption about 3.8 × 10-3 (mole/m2s),and the membrane prepared via 1600 °C sintering has the lowest carbon dioxide adsorption about 2.68 × 10-3 (mole/m2s).All of them have reusability and in long time operation, the membrane which was prepared via 1600 °C sintering has the smallest pores and also could operate for three days. After the test, the 1600 °C sintering ceramic hollow fiber membrane was most suitable for the factory.

Keywords: carbon dioxide capture, membrane contactor, ceramic membrane, ceramic hollow fiber membrane

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Authors: J. Ritonja, R. Brezovnik, M. Petrun, B. Polajžer

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Many modern synchronous generators in power systems are extremely weakly damped. The reasons are cost optimization of the machine building and introduction of the additional control equipment into power systems. Oscillations of the synchronous generators and related stability problems of the power systems are harmful and can lead to failures in operation and to damages. The only useful solution to increase damping of the unwanted oscillations represents the implementation of the power system stabilizers. Power system stabilizers generate the additional control signal which changes synchronous generator field excitation voltage. Modern power system stabilizers are integrated into static excitation systems of the synchronous generators. Available commercial power system stabilizers are based on linear control theory. Due to the nonlinear dynamics of the synchronous generator, current stabilizers do not assure optimal damping of the synchronous generator’s oscillations in the entire operating range. For that reason the use of the robust power system stabilizers which are convenient for the entire operating range is reasonable. There are numerous robust techniques applicable for the power system stabilizers. In this paper the use of sliding mode control for synchronous generator stability improvement is studied. On the basis of the sliding mode theory, the robust power system stabilizer was developed. The main advantages of the sliding mode controller are simple realization of the control algorithm, robustness to parameter variations and elimination of disturbances. The advantage of the proposed sliding mode controller against conventional linear controller was tested for damping of the synchronous generator oscillations in the entire operating range. Obtained results show the improved damping in the entire operating range of the synchronous generator and the increase of the power system stability. The proposed study contributes to the progress in the development of the advanced stabilizer, which will replace conventional linear stabilizers and improve damping of the synchronous generators.

Keywords: control theory, power system stabilizer, robust control, sliding mode control, stability, synchronous generator

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Authors: Bharat Kumar, Deepak Kumar, Vijay Chaudhry

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Zirconium alloys are used as core components of nuclear reactors due to their high wear resistance, good corrosion properties, and good mechanical stability at high temperatures. The present work simulates the contact between the calandria tube and the liquid injection shutdown system (LISS) nozzle. The Calandria tube is the outer covering of the pressure tube. Water flows inside the pressure tube through fuel claddings which produces vibration in the pressure tube along with vibration in the calandria tube. Fretting wear takes place at the point of contact between the calandria tube and the LISS nozzle. Fretting tests were performed under different conditions, such as; varying fretting duration (i.e., 1 to 4 hours), varying frequency (i.e., 5 to 6.5 Hz), and varying amplitude (100 to 400 µm). The formation of the oxide layer was observed during the fretting wear test; as a result, the worn product. The worn surfaces were analyzed with scanning electron microscopy (SEM) to analyze the wear mechanism involved in the fretting test, and Energy dispersive x-ray spectroscopy (EDS) and Raman spectroscopy were used to confirm the presence of an oxide layer on the worn surface. The oxide layer becomes more uniform with fretting duration in case of water submerged condition as compared to dry contact condition. The oxide layer is deeply removed at high amplitude due to the change of wear mechanism from adhesion to abrasion, as confirmed by the presence of micro ploughing and micro cutting. Low amplitude fretting favors the formation of the tribo-oxide layer.

Keywords: tribo-oxide layer, wear, mechanically mixed layer, zircaloy

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Authors: S. Hehni Meidani Behzad, Mokhtari Karchegani Amir, Mabodi Samad

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There are some TLE (Transfer Line Exchanger) that their lifetime reduced to 4 years instead of 30 years and after 4 years, we saw corroded area on one part of those T.L.E. that named Oval header and this happened in condition that other parts of those TLE were safe and perfect. By using of thickness measurement devices, we find that thickness reduces unusually on that part and after research and doing computer analysis with fluent software, it was recognized that on that part, we have high temperature and when this out of range temperature adds to bad quality of water, corrosion increased with high rate on that part and after more research it became obviously that it case by more excess air in furnace that located before this T.L.E. that this more air case to consuming more fuel to reach same furnace temperature so it concluded that inner coil fluid temperature increased and after received to T.L.E, this case happened and deflector condition, creep in coil and material analysis confirmed that condition.

Keywords: Transfer Line Exchanger (TLE), CFD, corrosion, erosion, tube, oval header

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Authors: Nassima Khanfri, Ali Boucenna

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As metallic nanoparticles are increasingly used in many economic sectors, there is interest in the biological and environmental safety of their production. The main methods of synthesizing nanoparticales are chemical and physical approaches that are often expensive and potentially harmful to the environment. The present study is devoted to the possibility of the synthesis of silver nanoparticales and zinc oxide from silver nitrate and zinc acetate using basilica plant extracts. The products obtained are characterized by various analysis techniques, such as UV/V, XRD, MEB-EDX, FTIR, and RAMAN. These analyzes confirm the crystalline nature of AgNps and ZnONps. These crystalline powders having effective biological activities regarding the antioxidant and antibacterial, which could be used in several biological applications.

Keywords: green synthesis, bio-reduction, metals nan Oparticales, Plants extracts

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Authors: Camille Aouinaït, Danilo Christen, Christoph Carlen

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Introduction: Small and Medium-sized Enterprises (SMEs) are facing different challenges such as pressures on environmental resources, the rise of downstream power, and trade liberalization. Remaining competitive by implementing innovations and engaging in collaborations could be a strategic solution. In Switzerland, the Federal Institute for Research in Agriculture (Agroscope), the Federal schools of technology (EPFL and ETHZ), Cantonal universities and Universities of Applied Sciences (UAS) can provide substantial inputs. UAS were developed with specific missions to match the labor markets and society needs. Research projects produce patents, publications and improved networks of scientific expertise. The study’s goal is to measure the contribution of UAS and research organization to innovation and the impact of collaborations with partners in the non-academic environment in Swiss traditional fruit production. Materials and methods: The European projects Traditional Food Network to improve the transfer of knowledge for innovation (TRAFOON) and Social Impact Assessment of Productive Interactions between science and society (SIAMPI) frame the present study. The former aims to fill the gap between the needs of traditional food producing SMEs and innovations implemented following European projects. The latter developed a method to assess the impacts of scientific research. On one side, interviews with market players have been performed to make an inventory of needs of Swiss SMEs producing apricots and berries. The participative method allowed matching the current needs and the existing innovations coming from past European projects. Swiss stakeholders (e.g. producers, retailers, an inter-branch organization of fruits and vegetables) directly rated the needs on a five-Likert scale. To transfer the knowledge to SMEs, training workshops have been organized for apricot and berries actors separately, on specific topics. On the other hand, a mapping of a social network is drawn to characterize the links between actors, with a focus on the Swiss canton of Valais and UAS Valais Wallis. Type and frequency of interactions among actors have identified thanks to interviews. Preliminary results: A list of 369 SMEs needs grouped in 22 categories was produced with 37 fulfilled questionnaires. Swiss stakeholders rated 31 needs very important. Training workshops on apricot are focusing on varietal innovations, storage, disease (bacterial blight), pest (Drosophila suzukii), sorting and rootstocks. Entrepreneurship was targeted through trademark discussions in berry production. The UAS Valais Wallis collaborated on a few projects with Agroscope along with industries, at European and national levels. Political and public bodies interfere with the central area of agricultural vulgarization that induces close relationships between the research and the practical side. Conclusions: The needs identified by Swiss stakeholders are becoming part of training workshops to incentivize innovations. The UAS Valais Wallis takes part in collaboration projects with the research environment and market players that bring innovations helping SMEs in their contextual environment. Then, a Strategic Research and Innovation Agenda will be created in order to pursue research and answer the issues facing by SMEs.

Keywords: agriculture, innovation, knowledge transfer, university and research collaboration

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Authors: M. Cortés, E. Vera, M. Avella

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Corrosion is an imminent process in nature, which affects all types of materials. In sewerage systems, the corrosion process caused by microorganisms, also known as biogenic sulfuric acid attack, has been studied. This affects the structural integrity of the concrete drainage pipes and the sewage treatment plants. This article is a review of research which focuses on the study of how to reduce the production of hydrogen sulfide, how to improve the resistance of concrete through the use of additives and the implementation of antimicrobial techniques to reduce bacterial growth.

Keywords: bactericides, biogenic sulfuric acid, corrosion, concrete, hydrogen sulphide, nano materials, zeolites

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Authors: Pauline Nyssen, Ange Mouithys-Mickalad, Maryse Hoebeke

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Inflammation is a complex physiological phenomenon involving chemical and enzymatic mechanisms. Polymorphonuclear neutrophil leukocytes (PMNs) play an important role by producing reactive oxygen species (ROS) and releasing myeloperoxidase (MPO), a pro-oxidant enzyme. Released both in the phagolysosome and the extracellular medium, MPO produces during its peroxidase and halogenation cycles oxidant species, including hypochlorous acid, involved in the destruction of pathogen agents, like bacteria or viruses. Inflammatory pathologies, like rheumatoid arthritis, atherosclerosis induce an excessive stimulation of the PMNs and, therefore, an uncontrolled release of ROS and MPO in the extracellular medium, causing severe damages to the surrounding tissues and biomolecules such as proteins, lipids, and DNA. The treatment of chronic inflammatory pathologies remains a challenge. For many years, MPO has been used as a target for the development of effective treatments. Numerous studies have been focused on the design of new drugs presenting more efficient MPO inhibitory properties. However, some designed inhibitors can be toxic. An alternative consists of assessing the potential inhibitory action of clinically-known molecules, having antioxidant activity. Propofol, 2,6-diisopropyl phenol, which is used as an intravenous anesthetic agent, meets these requirements. Besides its anesthetic action employed to induce a sedative state during surgery or in intensive care units, propofol and its injectable form Diprivan indeed present antioxidant properties and act as ROS and free radical scavengers. A study has also evidenced the ability of propofol to inhibit the formation of the neutrophil extracellular traps fibers, which are important to trap pathogen microorganisms during the inflammation process. The aim of this study was to investigate the potential inhibitory action mechanism of propofol and Diprivan on MPO activity. To go into the anti-inflammatory action of propofol in-depth, two of its oxidative derivatives, 2,6-diisopropyl-1,4-p-benzoquinone (PPFQ) and 3,5,3’,5’-tetra isopropyl-(4,4’)-diphenoquinone (PPFDQ), were studied regarding their inhibitory action. Specific immunological extraction followed by enzyme detection (SIEFED) and molecular modeling have evidenced the low anti-catalytic action of propofol. Stopped-flow absorption spectroscopy and direct MPO activity analysis have proved that propofol acts as a reversible MPO inhibitor by interacting as a reductive substrate in the peroxidase cycle and promoting the accumulation of redox compound II. Overall, Diprivan exhibited a weaker inhibitory action than the active molecule propofol. In contrast, PPFQ seemed to bind and obstruct the enzyme active site, preventing the trigger of the MPO oxidant cycles. PPFQ induced a better chlorination cycle inhibition at basic and neutral pH in comparison to propofol. PPFDQ did not show any MPO inhibition activity. The three interest molecules have also demonstrated their inhibition ability on an important step of the inflammation pathway, the PMNs superoxide anions production, thanks to EPR spectroscopy and chemiluminescence. In conclusion, propofol presents an interesting immunomodulatory activity by acting as a reductive substrate in the peroxidase cycle of MPO, slowing down its activity, whereas PPFQ acts more as an anti-catalytic substrate. Although PPFDQ has no impact on MPO, it can act on the inflammation process by inhibiting the superoxide anions production by PMNs.

Keywords: Diprivan, inhibitor, myeloperoxidase, propofol, spectroscopy

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Authors: R. Vishnu, K. S. Reddy, Amrendra Kumar

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The present guideline for the construction of flexible pavement in India, IRC 37: 2012 recommends to use viscous grade VG 40 bitumen in both wearing and binder bituminous layers. However, most of the bitumen production plants in India are unable to produce the air-blown VG40 grade bitumen. This requires plant’s air-blowing technique modification, and often the manufactures finds it as uneconomical. In this context, stiffer grade bitumen can be produced if bitumen is modified. Gilsonite, which is naturally occurring asphalt have been found to be used for increasing the stiffness of binders. The present study evaluates the physical, rheological characteristics of Gilsonite modified binders and the performance characteristics of these binders when used in the mix.

Keywords: bitumen, gilsonite, stiffness, laboratory evaluation

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Authors: Chandrakant Gurav, Md. Babar

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In the present study, an attempt is made to delineate the comparative morphometric analysis of Ambardi and Mangari watersheds of Kadvi and Kasari rivers sub-basins, Kolhapur District, Maharashtra India, using Geographical Information System (GIS) techniques. GIS is a computer assisted information method to store, analyze and display spatial data. Both the watersheds originate from Masai plateau of Jotiba- Panhala Hill range in Panhala Taluka of Kolhapur district. Ambardi watersheds cover 42.31 Sq. km. area and occur in northern hill slope, whereas Mangari watershed covers 54.63 Sq. km. area and occur on southern hill slope. Geologically, the entire study area is covered by Deccan Basaltic Province (DBP) of late Cretaceous to early Eocene age. Laterites belonging to late Pleistocene age also occur in the top of the hills. The objective of the present study is to carry out the morphometric parameters of watersheds, which occurs in differing slopes of the hill. Morphometric analysis of Ambardi watershed indicates it is of 4th order stream and Mangari watershed is of 5th order stream. Average bifurcation ratio of both watersheds is 5.4 and 4.0 showing that in both the watersheds streams flow from homogeneous nature of lithology and there is no structural controlled in development of the watersheds. Drainage density of Ambardi and Mangari watersheds is 3.45 km/km2 and 3.81 km/km2 respectively, and Stream Frequency is 4.51 streams/ km2 and 5.97 streams/ km2, it indicates that high drainage density and high stream frequency is governed by steep slope and low infiltration rate of the area for groundwater recharge. Textural ratio of both the watersheds is 6.6 km-1 and 9.6 km-1, which indicates that the drainage texture is fine to very fine. Form factor, circularity ratio and elongation ratios of the Ambardi and Mangari watersheds shows that both the watersheds are elongated in shape. The basin relief of Ambardi watershed is 447 m, while Mangari is 456 m. Relief ratio of Ambardi is 0.0428 and Mangari is 0.040. The ruggedness number of Ambardi is 1.542 and Mangari watershed is 1.737. The ruggedness number of both the watersheds is high which indicates the relief and drainage density is high.

Keywords: Ambardi, Deccan basalt, GIS, morphometry, Mangari, watershed

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Authors: Veriko Jeladze, Besarion Partsvania, Levan Shoshiashvili

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This paper addresses a very topical issue today. The frequency range 2.5-100 GHz contains frequencies that have already been used or will be used in modern 5G technologies. The wavelengths used in 5G systems will be close to the body dimensions of small size biological objects, particularly insects. Because the body and body parts dimensions of insects at these frequencies are comparable with the wavelength, the high absorption of EMF energy in the body tissues can occur(body resonance) and therefore can cause harmful effects, possibly the extinction of some of them. An investigation into the impact of radio-frequency nonionizing electromagnetic field (EMF) utilized in the future 5G on insects is of great importance as a very high number of 5G network components will increase the total EMF exposure in the environment. All ecosystems of the earth are interconnected. If one component of an ecosystem is disrupted, the whole system will be affected (which could cause cascading effects). The study of these problems is an important challenge for scientists today because the existing studies are incomplete and insufficient. Consequently, the purpose of this proposed research is to investigate the possible hazardous impact of RF-EMFs (including 5G EMFs) on insects. The project will study the effects of these EMFs on various insects that have different body sizes through computer modeling at frequencies from 2.5 to 100 GHz. The selected insects are honey bee, wasp, and ladybug. For this purpose, the detailed 3D discrete models of insects are created for EM and thermal modeling through FDTD and will be evaluated whole-body Specific Absorption Rates (SAR) at selected frequencies. All these studies represent a novelty. The proposed study will promote new investigations about the bio-effects of 5G-EMFs and will contribute to the harmonization of safe exposure levels and frequencies of 5G-EMFs'.

Keywords: electromagnetic field, insect, FDTD, specific absorption rate (SAR)

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Authors: Nishit L. Sanil, Raza M. Khan

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Increasing lift effectively at higher angles of attack has always been a daunting challenge in aviation especially on a delta wing. These are used on military jet fighter planes and has some undesirable characteristics, notably flow separation at high angles of attack and high drag at low speeds. In order to solve this problem, a design modification is modeled on a delta wing which would increase the lift so that we can improve maneuverability. To attain an increase in the lift of a 65 degree delta wing at higher angles of attack, a step-wise discontinuity is created at the upper surface of the delta wing. A normal delta wing is validated for comparison which would thereby give us a measure of flow separation and coefficient of lift affected by the modification. The results obtained deliver a significant increase in lift at higher angles of attack thereby delaying stall. Hence the benefits of the modification would aid the potential designs of aircraft’s in the time to come.

Keywords: coefficient of lift, delta wing, flow separation, step-wise discontinuity

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Authors: Lya Porto, Giulia Giacchè, Mario Aquino Alves

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The paper aims to describe the linkage between government and civil society proposing a study on agro-ecological agriculture policy and urban action in São Paulo city underling the main achievements obtained. The negotiation processes between social movements and the government (inputs) and its results on political regulation and public action for Urban Agriculture (UA) in São Paulo city (outputs) have been investigated. The method adopted is qualitative, with techniques of semi-structured interviews, participant observation, and documental analysis. The authors conducted 30 semi-structured interviews with organic farmers, activists, governmental and non-governmental managers. Participant observation was conducted in public gardens, urban farms, public audiences, democratic councils, and social movements meetings. Finally, public plans and laws were also analyzed. São Paulo city with around 12 million inhabitants spread out in a 1522 km2 is the economic capital of Brazil, marked by spatial and socioeconomic segregation, currently aggravated by environmental crisis, characterized by water scarcity, pollution, and climate changes. In recent years, Urban Agriculture (UA) social movements gained strength and struggle for a different city with more green areas, organic food production, and public occupation. As the dynamics of UA occurs by the action of multiple actresses and institutions that struggle to build multiple senses on UA, the analysis will be based on literature about solidarity economy, governance, public action and networks. Those theories will mark out the analysis that will emphasize the approach of inter-subjectivity built between subjects, as well as the hybrid dynamics of multiple actors and spaces in the construction of policies for UA. Concerning UA we identified four main typologies based on land ownership, main function (economic or activist), form of organization of the space, and type of production (organic or not). The City Hall registers 500 productive unities of agriculture, with around 1500 producers, but researcher estimated a larger number of unities. Concerning the social movements we identified three categories that differ in goals and types of organization, but all of them work by networks of activists and/or organizations. The first category does not consider themselves as a movement, but a network. They occupy public spaces to grow organic food and to propose another type of social relations in the city. This action is similar to what became known as the green guerrillas. The second is configured as a movement that is structured to raise awareness about agro-ecological activities. The third one is a network of social movements, farmers, organizations and politicians that work focused on pressure and negotiation with executive and legislative government to approve regulations and policies on organic and agro-ecological Urban Agriculture. We conclude by highlighting how the interaction among institutions and civil society produced important achievements for recognition and implementation of UA within the city. Some results of this process are awareness for local production, legal and institutional recognition of the rural zone around the city into the planning tool, the investment on organic school public procurements, the establishment of participatory management of public squares, the inclusion of UA on Municipal Strategic Plan and Master Plan.

Keywords: public action, policies, agroecology, urban and peri-urban agriculture, Sao Paulo

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Authors: Arda Ozkurt, Ozlem Bozkurt

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Brain-computer interfaces (BCIs) are devices that output commands by interpreting the data collected from the brain. Electroencephalography (EEG) is a non-invasive method to measure the brain's electrical activity. Since it was invented by Hans Berger in 1929, it has led to many neurological discoveries and has become one of the essential components of non-invasive measuring methods. Despite the fact that it has a low spatial resolution -meaning it is able to detect when a group of neurons fires at the same time-, it is a non-invasive method, making it easy to use without possessing any risks. In EEG, electrodes are placed on the scalp, and the voltage difference between a minimum of two electrodes is recorded, which is then used to accomplish the intended task. The recordings of EEGs include, but are not limited to, the currents along dendrites from synapses to the soma, the action potentials along the axons connecting neurons, and the currents through the synaptic clefts connecting axons with dendrites. However, there are some sources of noise that may affect the reliability of the EEG signals as it is a non-invasive method. For instance, the noise from the EEG equipment, the leads, and the signals coming from the subject -such as the activity of the heart or muscle movements- affect the signals detected by the electrodes of the EEG. However, new techniques have been developed to differentiate between those signals and the intended ones. Furthermore, an EEG device is not enough to analyze the data from the brain to be used by the BCI implication. Because the EEG signal is very complex, to analyze it, artificial intelligence algorithms are required. These algorithms convert complex data into meaningful and useful information for neuroscientists to use the data to design BCI devices. Even though for neurological diseases which require highly precise data, invasive BCIs are needed; non-invasive BCIs - such as EEGs - are used in many cases to help disabled people's lives or even to ease people's lives by helping them with basic tasks. For example, EEG is used to detect before a seizure occurs in epilepsy patients, which can then prevent the seizure with the help of a BCI device. Overall, EEG is a commonly used non-invasive BCI technique that has helped develop BCIs and will continue to be used to detect data to ease people's lives as more BCI techniques will be developed in the future.

Keywords: BCI, EEG, non-invasive, spatial resolution

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Authors: Zhengming Wu

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NanoFrazor lithography systems were developed as a first true alternative or extension to standard mask-less nanolithography methods like electron beam lithography (EBL). In contrast to EBL they are based on thermal scanning probe lithography (t-SPL). Here a heatable ultra-sharp probe tip with an apex of a few nm is used for patterning and simultaneously inspecting complex nanostructures. The heat impact from the probe on a thermal responsive resist generates those high-resolution nanostructures. The patterning depth of each individual pixel can be controlled with better than 1 nm precision using an integrated in-situ metrology method. Furthermore, the inherent imaging capability of the Nanofrazor technology allows for markerless overlay, which has been achieved with sub-5 nm accuracy as well as it supports stitching layout sections together with < 10 nm error. Pattern transfer from such resist features below 10 nm resolution were demonstrated. The technology has proven its value as an enabler of new kinds of ultra-high resolution nanodevices as well as for improving the performance of existing device concepts. The application range for this new nanolithography technique is very broad spanning from ultra-high resolution 2D and 3D patterning to chemical and physical modification of matter at the nanoscale. Nanometer-precise markerless overlay and non-invasiveness to sensitive materials are among the key strengths of the technology. However, while patterning at below 10 nm resolution is achieved, significantly increasing the patterning speed at the expense of resolution is not feasible by using the heated tip alone. Towards this end, an integrated laser write head for direct laser sublimation (DLS) of the thermal resist has been introduced for significantly faster patterning of micrometer to millimeter-scale features. Remarkably, the areas patterned by the tip and the laser are seamlessly stitched together and both processes work on the very same resist material enabling a true mix-and-match process with no developing or any other processing steps in between. The presentation will include examples for (i) high-quality metal contacting of 2D materials, (ii) tuning photonic molecules, (iii) generating nanofluidic devices and (iv) generating spintronic circuits. Some of these applications have been enabled only due to the various unique capabilities of NanoFrazor lithography like the absence of damage from a charged particle beam.

Keywords: nanofabrication, grayscale lithography, 2D materials device, nano-optics, photonics, spintronic circuits

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Authors: Robson da Cunha Santos, Caio Cezar R. Bonifacio, Diego Mureb Quesada, Gerson Gomes Cunha

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The paper is related to the safety of oil wells and environmental preservation on the planet, because they require great attention and commitment from oil companies and people who work with these equipments. This must occur from drilling the well until it is abandoned in order to safeguard the environment and prevent possible damage. The project had as main objective the constitution resulting from comparatives made among books, articles and publications with information gathered in technical visits to operational bases of Petrobras. After the visits, the information from methods of utilization and present managements, which were not available before, became available to the general audience. As a result, it is observed a huge flux of incorrect and out-of-date information that comprehends not only bibliographic archives, but also academic resources and materials. During the gathering of more in-depth information on the manufacturing, assembling, and use aspects of DHSVs, several issues that were previously known as correct, customary issues were discovered to be uncertain and outdated. Information of great importance resulted in affirmations about subjects as the depth of the valve installation that was before installed to 30 meters from the seabed (mud line). Despite this, the installation should vary in conformity to the ideal depth to escape from area with the biggest tendency to hydrates formation according to the temperature and pressure. Regarding to valves with nitrogen chamber, in accordance with books, they have their utilization linked to water line ≥ 700 meters, but in Brazilian exploratory fields, their use occurs from 600 meters of water line. The valves used in Brazilian fields are able to be inserted to the production column and self-equalizing, but the use of screwed valve in the column of production and equalizing is predominant. Although these valves are more expensive to acquire, they are more reliable, efficient, with a bigger shelf life and they do not cause restriction to the fluid flux. It follows that based on researches and theoretical information confronted to usual forms used in fields, the present project is important and relevant. This project will be used as source of actualization and information equalization that connects academic environment and real situations in exploratory situations and also taking into consideration the enrichment of precise and easy to understand information to future researches and academic upgrading.

Keywords: down hole safety valve, security devices, installation, oil-wells

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Authors: Nabil Jallouli, Luisa M. Pastrana-Martínez, Ana R. Ribeiro, Nuno F. F. Moreira, Joaquim L. Faria, Olfa Hentati, Adrián M. T. Silva, Mohamed Ksibi

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Degradation and mineralization of ibuprofen (IBU) were investigated using Ultraviolet (UV) Light Emitting Diodes (LEDs) in TiO2 photocatalysis. Samples of ultrapure water (UP) and a secondary treated effluent of a municipal wastewater treatment plant (WWTP), both spiked with IBU, as well as a highly concentrated IBU (230 mgL-1) pharmaceutical industry wastewater (PIWW), were tested in the TiO2/UV-LED system. Three operating parameters, namely, pH, catalyst load and number of LEDs were optimized. The process efficiency was evaluated in terms of IBU removal using high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, the mineralization was investigated by determining the dissolved organic carbon (DOC) content. The chemical structures of transformation products were proposed based on the data obtained using liquid chromatography with a high resolution mass spectrometer ion trap/time-of-flight (LC-MS-IT-TOF). A possible pathway of IBU degradation was accordingly proposed. Bioassays were performed using the marine bacterium Vibrio fischeri to evaluate the potential acute toxicity of original and treated wastewaters. TiO2 heterogeneous photocatalysis was efficient to remove IBU from UP and from PIWW, and less efficient in treating the wastewater from the municipal WWTP. The acute toxicity decreased by ca. 40% after treatment, regardless of the studied matrix.

Keywords: acute toxicity, Ibuprofen, UV-LEDs, wastewaters

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Authors: Dina Magdy Abdo, Ayat N. El-Shazly, E. A. Abdel-Aal

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Forward osmosis (FO) is one of the important processes during the wastewater treatment system for environmental remediation and fresh water regeneration. Both Egypt and China are troubled by over millions of tons of wastewater every year, including domestic and industrial wastewater. However, the traditional FO process in wastewater treatment usually suffers low efficiency and high energy consumption because of the continuously diluted draw solution. An additional concentration process is necessary to keep running of FO separation, causing energy waste. Based on the previous study on photothermal membrane, a sun-driven evaporation process is integrated into the draw solution side of FO system. During the sun-driven evaporation, not only the draw solution can be concentrated to maintain a stable and sustainable FO system, but fresh water can be directly separated for regeneration. Solar energy is the ultimate energy source of everything we have on Earth and is, without any doubt, the most renewable and sustainable energy source available to us. Additionally, the FO membrane process is rationally designed to limit the concentration polarization and fouling. The FO membrane’s structure and surface property will be further optimized by the adjustment of doping ratio of controllable nano-materials, membrane formation conditions, and selection of functional groups. A novel kind of nano-composite functional separation membrane with bi-interception layers and high hydrophilicity will be developed for the application in wastewater treatment. So, herein we aim to design a new wastewater treatment system include forward osmosis with high-efficiency energy recovery via the integration of photothermal membrane.

Keywords: forward osmosis, membrane, solar, water treatement

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Authors: Y. H. Hwang, J. Won, Y. S. Kang

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Supported ionic liquid membranes (SILMs) have attracted due to the negligible vapor pressure of ionic liquids (ILs) as well as the high gas selectivity for specific gases such as CO2 or olefin. 1-ethyl-3-methylimidazolium tricyanomethanide ([EMIM][TCM]), 1-butyl-3-methylimidazolium tricyanomethanide ([BMIM][TCM]), show high CO2 solubility, CO2 absorption, rapid CO2 absorption rate and negligible vapor pressure, SILMs using these ILs have been good candidates as CO2 separation membranes. However, SILM has to be operated at a low differential pressure to prevent the solvent from being expelled from the pores of supported membranes. In this paper, we improve the mechanical strength by forming ion gels which provide the stability while it retains the diffusion properties of the liquid stage which affects the gas separation properties. The ion gel was created by the addition of tri-block copolymer, poly(styrene-ethylene oxide-b-styrene) in RTIL. SILM using five different RTILs, are investigated with and without ion gels. The gas permeance were measured and the gas performance with and without the SEOS were investigated.

Keywords: ion gel, ionic liquid, membrane, nanostructure

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Authors: Yingqian Chen, Sergei Manzhos

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Organic electrodes are a way to achieve high rate (high power) and environment-friendly batteries. We present a computational density functional theory study of Li and Na storage in tetracyanoethylene based molecular and crystalline materials. Up to five Li and Na atoms can be stored on TCNE chemisorbed on doped graphene (corresponding to ~1000 mAh/gTCNE), with binding energies stronger than cohesive energies of the Li and Na metals by 1-2 eV. TCNE has been experimentally shown to form a crystalline material with Li with stoichiometry Li-TCNE. We confirm this computationally and also predict that a similar crystal based of Na-TCNE is also stable. These crystalline materials have well defined channels for facile Li or Na ion insertion and diffusion. Specifically, Li and Na binding energies in Li-TCNE and Na-TCNE crystals are about 1.5 eV and stronger than the cohesive energy of Li and Na, respectively. TCNE immobilized on conducting graphene-based substrates and Li/Na-TCNE crystals could therefore become efficient anode materials for organic Li and Na ion batteries, with which it should also be possible to avoid reduction of common battery electrolytes.

Keywords: organic ion batteries, tetracyanoethylene, cohesive energies, electrolytes

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Authors: Ku Aina Afiqah Ku Adzman, Manmeet Mahinderjit Singh, Zarul Fitri Zaaba

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NFC operates on low-range 13.56 MHz frequency within a distance from 4cm to 10cm, and the applications can be categorized as touch and go, touch and confirm, touch and connect, and touch and explore. NFC applications are vulnerable to various security and privacy attacks such due to its physical nature; unprotected data stored in NFC tag and insecure communication between its applications. This paper aims to determine the likelihood of security risks happening in an NFC technology and application. We present an NFC technology taxonomy covering NFC standards, types of application and various security and privacy attack. Based on observations and the survey presented to evaluate the risk assessment within the touch and go application demonstrates two security attacks that are high risks namely data corruption and DOS attacks. After the risks are determined, risk countermeasures by using AHP is adopted. The guideline and solutions to these two high risks, attacks are later applied to a secure NFC-enabled Smartphone Attendance System.

Keywords: Near Field Communication (NFC), risk assessment, multi-criteria decision making, Analytical Hierarchy Process (AHP)

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Authors: Maria Luisa de la Torre, Javier Aroba, Jose Miguel Davila, Aguasanta M. Sarmiento

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Steel is one of the most widely used materials in polymetallic sulfide mining installations. One of the main problems suffered by these facilities is the economic losses due to the corrosion of this material, which is accelerated and aggravated by the contact with acid waters generated in these mines when sulfides come into contact with oxygen and water. This generation of acidic water, in turn, is accelerated by the presence of acidophilic bacteria. In order to gain a more detailed understanding of this corrosion process and the interaction between steel and acidic water, a laboratory experiment was carried out in which carbon steel plates were introduced into four different solutions for 27 days: distilled water (BK), which tried to assimilate the effect produced by rain on this material, an acid solution from a mine with a high Fe2+/Fe3+ (PO) content, another acid solution of water from another mine with a high Fe3+/Fe2+ (PH) content and, finally, one that reproduced the acid mine water with a high Fe2+/Fe3+ content but in which there were no bacteria (ST). Every 24 hours, physicochemical parameters were measured, and water samples were taken to carry out an analysis of the dissolved elements. The results of these measurements were processed using an explainable AI model based on fuzzy logic. It could be seen that, in all cases, there was an increase in pH, as well as in the concentrations of Fe and, in particular, Fe(II), as a consequence of the oxidation of the steel plates. Proportionally, the increase in Fe concentration was higher in PO and ST than in PH because Fe precipitates were produced in the latter. The rise of Fe(II) was proportionally much higher in PH, especially in the first hours of exposure, because it started from a lower initial concentration of this ion. Although to a lesser extent than in PH, the greater increase in Fe(II) also occurred faster in PO than in ST, a consequence of the action of the catalytic bacteria. On the other hand, Cu concentrations decreased throughout the experiment (with the exception of distilled water, which initially had no Cu, as a result of an electrochemical process that generates a precipitation of Cu together with Fe hydroxides. This decrease is lower in PH because the high total acidity keeps it in solution for a longer time. With the application of an artificial intelligence tool, it has been possible to evaluate the effects of steel corrosion in mining environments, corroborating and extending what was obtained by means of classical statistics.

Keywords: acid mine drainage, artificial intelligence, carbon steel, corrosion, fuzzy logic

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Authors: Chung-Yu Wu, Chia-Chi Chang, Wei-Ming Chen, Pu-Wei Wu, Shih-Fan Chen, Po-Chun Chen

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Electrostimulation medical devices for neural diseases require electroactive and biocompatible materials to transmit signals from electrodes to targeting tissues. Protection of surrounding tissues has become a great challenge for long-term implants. In this study, we designed back-end processes with compatible, efficient, and reliable advantages over the current state-of-the-art. We explored a hermetic packaging process with high quality of adhesion and uniformity as the biocompatible devices for long-term implantation. This approach is able to provide both excellent biocompatibility and protection to the biomedical electronic devices by performing conformal coating of biocompatible materials. We successfully developed a packaging process that is capable of exposing the stimulating electrode and cover all other faces of chip with high quality of protection to prevent leakage of devices and body fluid.

Keywords: biocompatible package, medical microelectronics, surface coating, long-term implantation

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Authors: Fatima Ammari, Meriem Chenouf

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Synthesis of gold nanoparticles (AuNPs) has attracted much attention since the pioneering discovery of the high catalytic activity of supported gold nanoparticles in the reaction of CO oxidation at low temperature. In this research field, we used montmorillonite pre-acidified under gentle conditions for AuNPs stabilization; using different loading percentage 1, 2 and 5%. The gold nanoparticles were obtained using chemical reduction method using NaBH4 as reductant agent. The obtained gold nanoparticles stabilized in acid-activated montmorillonite were used as catalysts for reduction of 4-nitrophenol to aminophenol with sodium borohydride at room temperature The UV-Vis results confirm directly the gold nanaoparticles formation. The XRD N2 adsorption and MET results showed the formation of gold nanoparticles in the pores of preacidified montmorillonite with an average size of 5.7nm. The reduction reaction of 4-nitrophenol into 4-aminophenol with NaBH4 catalyzed by Au°-montmorillonite catalyst exhibits remarkably a high activity; the reaction was completed within 4.5min.

Keywords: gold, acid-activated montmorillonite, nanoparticles, 4-nitrophenol

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Authors: Corazon Virtudazo-Ligaray, Mark Daniel G. de Luna, Meng-Wei Wan, Ming-Chun Lu

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A series of ternary compound catalyst with nanocomposites of ceria, tungsten trioxide and titania (CeO2-WOx-TiO2) with different WOx mole fraction (10, 20, 30, 40) have been synthesized by sol-gel method. These nanocomposite catalysts were used for oxidative extractive desulfurization of model fuel oil, which were composed of dibenzothiophene (DBT) dissolved in toluene. The 30% hydrogen peroxide, H2O2 was used as oxidant and acetonitrile as extractant. These catalysts were characterized by SEM-EDS to determine the morphology. Catalytic oxidation results show that the catalysts have high selectivity in refractory fuel oil with organo sulfur contents. The oxidative removal of DBT increases as the HPW content increases. The nanocomposites CeO2-WOx-TiO2 also shows high selectivity for DBT oxidation in the DBT–toluene acetonitrile system. The catalytic oxidative desulfurization ratio of model fuel reached to 100% with nanocomposites CeO2-WOx-TiO2 (35-30-35) mol percent catalyst nanocomposition under 333 K in 30 minutes.

Keywords: ceria, oxidative desulfurization, titania, phosphotungstic acid

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Authors: Lawrence Gumbe

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Kenya Vision 2030 is the country's programme for transformation covering the period 2008 to 2030. Its objective is to help transform Kenya into a newly industrializing, middle-income, exceeding US$10000, country providing a high quality of life to all its citizens by 2030, in a clean and secure environment. Increased agricultural and production and productivity is crucial for the realization of Vision 2030. Mechanization of agriculture in order to achieve greater yields is the only way to achieve these objectives. There are contending groups and views on the strategy for agricultural mechanization. The first group are those who oppose the widespread adoption of advanced technologies (mostly internal combustion engines and tractors) in agricultural mechanization as entirely inappropriate in most situations in developing countries. This group argues that mechanically powered -agricultural mechanization often leads to displacement of labour and hence increased unemployment, and this results in a host of other socio-economic problems, amongst them, rural-urban migration, inequitable distribution of wealth and in many cases an increase in absolute poverty, balance of payments due to the need to import machinery, fuel and sometimes technical assistance to manage them. The second group comprises of those who view the use of the improved hand tools and animal powered technology as transitional step between the most rudimentary step in technological development (characterized by entire reliance on human muscle power) and the advanced technologies (characterized 'by reliance on tractors and other machinery). The third group comprises those who regard these intermediate technologies (ie. improved hand tools and draught animal technology in agriculture) as a ‘delaying’ tactic and they advocate the use of mechanical technologies as-the most appropriate. This group argues that alternatives to the mechanical technologies do not just exist as a practical matter, or, if they are available, they are inefficient and they cannot be compared to the mechanical technologies in terms of economics and productivity. The fourth group advocates a compromise between groups two and third above. This group views the improved hand tools and draught animal technology as more of an 18th century technology and the modem tractor and combine harvester as too advanced for developing countries. This group has been busy designing an ‘intermediate’, ‘appropriate’, ‘mini’, ‘micro’ tractor for use by farmers in developing countries. This paper analyses and concludes on the different agricultural mechanization strategies available to Kenya and other third world countries

Keywords: agriculture, mechanazation, transformation, industrialization

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Authors: Preetham Shankapal, Jill King, Kori Murray, Corby Martin, Paula Giselman, Jason Hicks, Owen Carmicheal

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Activation of reward and satiety networks in the brain while processing palatable food cues, as well as functional connectivity during rest has been studied using functional Magnetic Resonance Imaging of the brain in various obesity phenotypes. However, functional connectivity within the reward and satiety network during food cue processing is understudied. 14 obese individuals underwent two fMRI scans during viewing of Macronutrient Picture System images. Each scan included two blocks of images of High Sugar/High Fat (HSHF), High Carbohydrate/High Fat (HCHF), Low Sugar/Low Fat (LSLF) and also non-food images. Seed voxels within seven food reward relevant ROIs: Insula, putamen and cingulate, precentral, parahippocampal, medial frontal and superior temporal gyri were isolated based on a prior meta-analysis. Beta series correlation for task-related functional connectivity between these seed voxels and the rest of the brain was computed. Voxel-level differences in functional connectivity were calculated between: first and the second scan; individuals who saw novel (N=7) vs. Repeated (N=7) images in the second scan; and between the HC/HF, HSHF blocks vs LSLF and non-food blocks. Computations and analysis showed that during food image viewing, reward network ROIs showed significant functional connectivity with each other and with other regions responsible for attentional and motor control, including inferior parietal lobe and precentral gyrus. These functional connectivity values were heightened among individuals who viewed novel HS/HF images in the second scan. In the second scan session, functional connectivity was reduced within the reward network but increased within attention, memory and recognition regions, suggesting habituation to reward properties and increased recollection of previously viewed images. In conclusion it can be inferred that Functional Connectivity within reward network and between reward and other brain regions, varies by important experimental conditions during food photography viewing, including habituation to shown foods.

Keywords: fMRI, functional connectivity, task-based, beta series correlation

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Authors: Arnab Majumdar, Sanjoy Sadhukhan

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Although gun barrel steels are an important variety from defense view point, available literatures are very limited. In the present work, an IF grade Ni-Cr-Mo-V high strength low alloy steel is produced in Electric Earth Furnace-ESR Route. Ingot was hot forged to desired dimension with a reduction ratio of 70-75% followed by homogenization, hardening and tempering treatment. Sample chemistry, NMIR, macro and micro structural analyses were done. Mechanical properties which include tensile, impact, and fracture toughness were studied. Ultrasonic testing was done to identify internal flaws. The existing high strength low alloy Ni-Cr-Mo-V steel shows improved properties in modified processing route and heat treatment schedule in comparison to properties noted earlier for manufacturing of gun barrels. The improvement in properties seems to withstand higher explosive loads with the same amount of steel in gun barrel application.

Keywords: gun barrel steels, IF grade, chemistry, physical properties, thermal and mechanical processing, mechanical properties, ultrasonic testing

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Authors: Mikko Salminen, Niklas Ravaja

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Emotional intelligence (EI) consists of skills for monitoring own emotions and emotions of others, skills for discriminating different emotions, and skills for using this information in thinking and actions. EI enhances, for example, work outcomes and organizational climate. We suggest that the role and manifestations of EI should also be studied in real leadership situations, especially during the emotional, social interaction. Leadership is essentially a process to influence others for reaching a certain goal. This influencing happens by managerial processes and computer-mediated communication (e.g. e-mail) but also by face-to-face, where facial expressions have a significant role in conveying emotional information. Persons with high EI are typically perceived more positively, and they have better social skills. We hypothesize, that during social interaction high EI enhances the ability to detect other’s emotional state and controlling own emotional expressions. We suggest, that emotionally intelligent leader’s experience less stress during social leadership situations, since they have better skills in dealing with the related emotional work. Thus the high-EI leaders would be more able to enjoy these situations, but also be more efficient in choosing appropriate expressions for building constructive dialogue. We suggest, that emotionally intelligent leaders show more positive emotional expressions than low-EI leaders. To study these hypotheses we observed performance review discussions of 40 leaders (24 female) with 78 (45 female) of their followers. Each leader held a discussion with two followers. Psychophysiological methods were chosen because they provide objective and continuous data from the whole duration of the discussions. We recorded sweating of the hands (electrodermal activation) by electrodes placed to the fingers of the non-dominant hand to assess the stress-related physiological arousal of the leaders. In addition, facial electromyography was recorded from cheek (zygomaticus major, activated during e.g. smiling) and periocular (orbicularis oculi, activated during smiling) muscles using electrode pairs placed on the left side of the face. Leader’s trait EI was measured with a 360 questionnaire, filled by each leader’s followers, peers, managers and by themselves. High-EI leaders had less sweating of the hands (p = .007) than the low-EI leaders. It is thus suggested that the high-EI leaders experienced less physiological stress during the discussions. Also, high scores in the factor “Using of emotions” were related to more facial muscle activation indicating positive emotional expressions (cheek muscle: p = .048; periocular muscle: p = .076, almost statistically significant). The results imply that emotionally intelligent managers are positively relaxed during s social leadership situations such as a performance review discussion. The current study also highlights the importance of EI in face-to-face social interaction, given the central role facial expressions have in interaction situations. The study also offers new insight to the biological basis of trait EI. It is suggested that the identification, forming, and intelligently using of facial expressions are skills that could be trained during leadership development courses.

Keywords: emotional intelligence, leadership, performance review discussion, psychophysiology, social interaction

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Authors: Talat Baran

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The Suzuki C(sp2)-C(sp2) coupling reaction is considered to be one of the best ways for the synthesis of biaryl compounds. There are many studies reporting the catalytic performance of palladium catalyst in Suzuki coupling reactions. Natural biopolymer (such as zeolite, carbon, silica, and chitosan) supporting catalysts have been lately attracted interest because of their low-cost, nontoxicity, and eco-friendliness. One of the most important natural biopolymer is cellulose, which is widely considered as an eco-friendly biopolymer due to its biodegradable, non-toxic and renewable nature. In this study, (1) cellulose supported Pd(II) catalyst was synthesized (2) its chemical structure was characterized by FT-IR, SEM/EDAX, XRD, TG-DTG, ICP-OES techniques (3) to investigate the performance of the catalyst in Suzuki coupling reactions by using microwave irradiation technique (4) reusability of the catalyst was done under optimum conditions. This cellulose supported Pd(II) catalyst exhibited high selectivity and efficiency in Suzuki coupling reactions under mild conditions (50°C). High TON and TOF values were recorded for the catalyst. Also, the reusability tests showed the catalysts could be used for several times in consequence of reusability tests.

Keywords: palladium, cellulose, Schiff base, reusability

Procedia PDF Downloads 255