Search results for: solar assisted adsorption chiller
2382 Optimization of Hydrogel Conductive Nanocomposite as Solar Cell
Authors: Shimaa M. Elsaeed, Reem K. Farag, Ibrahim M. Nassar
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Hydrogel conductive polymer nanocomposite fabricated via in-situ polymerization of polyaniline (PANI) inside thermosensitive hydrogels based on hydroxy ethyl meth acrylate (HEMA) copolymer with 2-acrylamido-2-methyl propane sulfonic acid (AMPS). SEM micrographs show the nanometric size of the conductive material (polyaniline, PANI) dispersed in the hydrogel matrix. The swelling parameters of hydrogel are measured. The incorporation of PANI improves the mechanical properties and swelling up to 30,000% without breaking. X-ray diffraction shows that typical polyaniline crystallization is formed in composite, which is advantageous to increase the electrical conductivity of the composite hydrogel. Open-circuit voltage (I-V) curve fill factor of the highest photo-conversion efficiency and enhanced to use in solar cell.Keywords: hydrogel, solar cell, conductive polymer, nanocomposite
Procedia PDF Downloads 3922381 Evaluation of PV Orientation Effect on Mismatch between Consumption Load and PV Power Profiles
Authors: Iyad M. Muslih, Yehya Abdellatif, Sara Qutishat
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Renewable energy and in particular solar photovoltaic energy is emerging as a reasonable power generation source. The intermittent and unpredictable nature of solar energy can represent a serious challenge to the utility grids, specifically at relatively high penetration. To minimize the impact of PV power systems on the grid, self-consumption is encouraged. Self-consumption can be improved by matching the PV power generation with the electrical load consumption profile. This study will focus in studying different load profiles and comparing them to typical solar PV power generation at the selected sites with the purpose of analyzing the mismatch in consumption load profile for different users; residential, commercial, and industrial versus the solar photovoltaic output generation. The PV array orientation can be adjusted to reduce the mismatch effects. The orientation shift produces a corresponding shift in the energy production curve. This shift has a little effect on the mismatch for residential loads due to the fact the peak load occurs at night due to lighting loads. This minor gain does not justify the power production loss associated with the orientation shift. The orientation shift for both commercial and industrial cases lead to valuable decrease in the mismatch effects. Such a design is worth considering for reducing grid penetration. Furthermore, the proposed orientation shift yielded better results during the summer time due to the extended daylight hours.Keywords: grid impact, HOMER, power mismatch, solar PV energy
Procedia PDF Downloads 5982380 A Daily Diary Study on Technology-Assisted Supplemental Work, Psychological Detachment, and Well-Being – The Mediating Role of Cognitive Coping
Authors: Clara Eichberger, Daantje Derks, Hannes Zacher
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Technology-assisted supplemental work (TASW) involves performing job-related tasks after regular working hours with the help of technological devices. Due to emerging information and communication technologies, such behavior becomes increasingly common. Since previous research on the relationship of TASW, psychological detachment and well-being are mixed, this study aimed to examine the moderating roles of appraisal and cognitive coping. A moderated mediation model was tested with daily diary data from 100 employees. As hypothesized, TASW was positively related to negative affect at bedtime. In addition, psychological detachment mediated this relationship. Results did not confirm appraisal and cognitive coping as moderators. However, additional analyses revealed cognitive coping as a mediator of the positive relationship of TASW and positive affect at bedtime. These results suggest that, on the one hand engaging in TASW can be harmful to employee well-being (i.e., more negative affect) and on the other hand, it can also be associated with higher well-being (i.e., more positive affect) in case it is accompanied by cognitive coping.Keywords: cognitive coping, psychological detachment, technology-assisted supplemental work, well-being
Procedia PDF Downloads 1812379 Density Functional Theory Study of the Surface Interactions between Sodium Carbonate Aerosols and Fission Products
Authors: Ankita Jadon, Sidi Souvi, Nathalie Girault, Denis Petitprez
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The interaction of fission products (FP) with sodium carbonate (Na₂CO₃) aerosols is of a high safety concern because of their potential role in the radiological source term mitigation by FP trapping. In a sodium-cooled fast nuclear reactor (SFR) experiencing a severe accident, sodium (Na) aerosols can be formed after the ejection of the liquid Na coolant inside the containment. The surface interactions between these aerosols and different FP species have been investigated using ab-initio, density functional theory (DFT) calculations using Vienna ab-initio simulation package (VASP). In addition, an improved thermodynamic model has been proposed to treat DFT-VASP calculated energies to extrapolate them to temperatures and pressures of interest in our study. A combined experimental and theoretical chemistry study has been carried out to have both atomistic and macroscopic understanding of the chemical processes; the theoretical chemistry part of this approach is presented in this paper. The Perdew, Burke, and Ernzerhof functional were applied in combination with Grimme’s van der Waals correction to compute exchange-correlational energy at 0 K. Seven different surface cleavages were studied of Ƴ-Na₂CO₃ phase (stable at 603.15 K), it was found that for defect-free surfaces, the (001) facet is the most stable. Furthermore, calculations were performed to study surface defects and reconstructions on the ideal surface. All the studied surface defects were found to be less stable than the ideal surface. More than one adsorbate-ligand configurations were found to be stable confirming that FP vapors could be trapped on various adsorption sites. The calculated adsorption energies (Eads, eV) for the three most stable adsorption sites for I₂ are -1.33, -1.088, and -1.085. Moreover, the adsorption of the first molecule of I₂ changes the surface in a way which would favor stronger adsorption of a second molecule of I2 (Eads, eV = -1.261). For HI adsorption, the most favored reactions have the following Eads (eV) -1.982, -1.790, -1.683 implying that HI would be more reactive than I₂. In addition to FP species, adsorption of H₂O was also studied as the hydrated surface can have different reactivity than the bare surface. One thermodynamically favored site for H₂O adsorption was found with an Eads, eV of -0.754. Finally, the calculations of hydrated surfaces of Na₂CO₃ show that a layer of water adsorbed on the surface significantly reduces its affinity for iodine (Eads, eV = -1.066). According to the thermodynamic model built, the required partial pressure at 373 K to have adsorption of the first layer of iodine is 4.57×10⁻⁴ bar. The second layer will be adsorbed at partial pressures higher than 8.56×10⁻⁶ bar; a layer of water on the surface will increase these pressure almost ten folds to 3.71×10⁻³ bar. The surface interacts with elemental Cs with an Eads (eV) of -1.60, while interacts even strongly with CsI with an Eads (eV) of -2.39. More results on the interactions between Na₂CO₃ (001) and cesium-based FP will also be presented in this paper.Keywords: iodine uptake, sodium carbonate surface, sodium-cooled fast nuclear reactor, DFT calculations, fission products
Procedia PDF Downloads 1442378 Kinetics and Mechanism Study of Photocatalytic Degradation Using Heterojunction Semiconductors
Authors: Ksenija Milošević, Davor Lončarević, Tihana Mudrinić, Jasmina Dostanić
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Heterogeneous photocatalytic processes have gained growing interest as an efficient method to generate hydrogen by using clean energy sources and degrading various organic pollutants. The main obstacles that restrict efficient photoactivity are narrow light-response range and high rates of charge carrier recombination. The formation of heterojunction by combining a semiconductor with low VB and a semiconductor with high CB and a suitable band gap was found to be an efficient method to prepare more sensible materials with improved charge separation, appropriate oxidation and reduction ability, and enhanced visible-light harvesting. In our research, various binary heterojunction systems based on the wide-band gap (TiO₂) and narrow bandgap (g-C₃N₄, CuO, and Co₂O₃) photocatalyst were studied. The morphology, optical, and electrochemical properties of the photocatalysts were analyzed by X-ray diffraction (XRD), scanning electron microscopy (FE-SEM), N₂ physisorption, diffuse reflectance measurements (DRS), and Mott-Schottky analysis. The photocatalytic performance of the synthesized catalysts was tested in single and simultaneous systems. The synthesized photocatalysts displayed good adsorption capacity and enhanced visible-light photocatalytic performance. The mutual interactions of pollutants on their adsorption and degradation efficiency were investigated. The interfacial connection between photocatalyst constituents and the mechanism of the transport pathway of photogenerated charge species was discussed. A radical scavenger study revealed the interaction mechanisms of the photocatalyst constituents in single and multiple pollutant systems under solar and visible light irradiation, indicating the type of heterojunction system (Z scheme or type II).Keywords: bandgap alignment, heterojunction, photocatalysis, reaction mechanism
Procedia PDF Downloads 962377 The Heating Prosumer: Optimal Simultaneous Use of Heat-Pumps and Solar Panels
Authors: Youssef El Makhrout, Aude Pommeret, Tunç Durmaz
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This paper analyses the consequences of a heat pump on the optimal behavior of a prosumer. A theoretical microeconomic model is developed for household heating and electricity consumption to analyze the profitability of installing a solar PV system with a heat pump, battery storage, and grid use. The aim is to present the optimal scenario of investment in renewable energy equipment to cover domestic and heating needs. Simulation data of a French house of 170m² in Chambery are used in this paper. The house is divided into 5 zones with 3 heated zones of 89.4 m² occupied by two people. The analysis is based on hourly data for one year, from 00:00 01/01/2021 to 23:00 31/12/2021. Results indicate that without taking the cost of materials and no financial aid, the most profitable scenario for a household is when he owns solar panels, a heat pump, and battery storage. However, with the costs and financial aid of the French government for energy renovation, the net economic surplus change and the profitability during 20 years are important when the household decides to add a heat pump to existing solar panels. In this scenario, the household can realize 35.84% as a surplus change improvement, but this cannot cover all installation costs. The household can get benefits and cover all installation costs after exploiting financial support in the case of adopting a heat pump. The investment in a battery is still not profitable because of its high cost and the lack of financial aid. Some public policy recommendations are proposed, especially for solar panels and battery storage.Keywords: household’s heating, prosumer, electricity consumption, renewable energy, welfare gain, comfort, solar PV, heat pumps, storage
Procedia PDF Downloads 602376 Microwave-Assisted Synthesis of a Class of Pyridine and Purine Thioglycoside Analogs
Authors: Mamdouh Abu-Zaied, K. Mohamed, Galal A. Nawwar
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Microwave-assisted synthesis of a new class of pyridine or purine thioglycoside analogs from readily available starting materials has been described. The key step of this protocol is the formation of sodium pyridine 4-thiolate 4 and pyrazolo[1,5-a]pyrimidine-7-thiolate 5 derivatives via condensation of 1 with cyanoacetanilide derivative 2 or 5-aminopyrazole derivative 3 respectively under microwave irradiation, followed by coupling with halo sugars to give the corresponding pyridine and purine thioglycoside analogs. The obtained compounds were evaluated in vitro against lung (A549), colon (HCT116), liver (HEPG2), and MCF-7(breast) cancer cell lines. Some of them recorded promising activities.Keywords: antitumor, cyclic sugars, pyrazoles, pyridines, pyrimidines, purines, thioglycosides
Procedia PDF Downloads 2342375 Robotic Assisted vs Traditional Laparoscopic Partial Nephrectomy Peri-Operative Outcomes: A Comparative Single Surgeon Study
Authors: Gerard Bray, Derek Mao, Arya Bahadori, Sachinka Ranasinghe
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The EAU currently recommends partial nephrectomy as the preferred management for localised cT1 renal tumours, irrespective of surgical approach. With the advent of robotic assisted partial nephrectomy, there is growing evidence that warm ischaemia time may be reduced compared to the traditional laparoscopic approach. There is still no clear differences between the two approaches with regards to other peri-operative and oncological outcomes. Current limitations in the field denote the lack of single surgeon series to compare the two approaches as other studies often include multiple operators of different experience levels. To the best of our knowledge, this study is the first single surgeon series comparing peri-operative outcomes of robotic assisted and laparoscopic PN. The current study aims to reduce intra-operator bias while maintaining an adequate sample size to assess the differences in outcomes between the two approaches. We retrospectively compared patient demographics, peri-operative outcomes, and renal function derangements of all partial nephrectomies undertaken by a single surgeon with experience in both laparoscopic and robotic surgery. Warm ischaemia time, length of stay, and acute renal function deterioration were all significantly reduced with robotic partial nephrectomy, compared to laparoscopic nephrectomy. This study highlights the benefits of robotic partial nephrectomy. Further prospective studies with larger sample sizes would be valuable additions to the current literature.Keywords: partial nephrectomy, robotic assisted partial nephrectomy, warm ischaemia time, peri-operative outcomes
Procedia PDF Downloads 1322374 Signal Processing Approach to Study Multifractality and Singularity of Solar Wind Speed Time Series
Authors: Tushnik Sarkar, Mofazzal H. Khondekar, Subrata Banerjee
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This paper investigates the nature of the fluctuation of the daily average Solar wind speed time series collected over a period of 2492 days, from 1st January, 1997 to 28th October, 2003. The degree of self-similarity and scalability of the Solar Wind Speed signal has been explored to characterise the signal fluctuation. Multi-fractal Detrended Fluctuation Analysis (MFDFA) method has been implemented on the signal which is under investigation to perform this task. Furthermore, the singularity spectra of the signals have been also obtained to gauge the extent of the multifractality of the time series signal.Keywords: detrended fluctuation analysis, generalized hurst exponent, holder exponents, multifractal exponent, multifractal spectrum, singularity spectrum, time series analysis
Procedia PDF Downloads 3832373 Feasibility Study of a Solar Farm Project with an Executive Approach
Authors: Amir Reza Talaghat
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Since 2015, a new approach and policy regarding energy resources protection and using renewable energies has been started in Iran which was developing new projects. Investigating about the feasibility study of these new projects helped to figure out five steps to prepare an executive feasibility study of the concerned projects, which are proper site selections, authorizations, design and simulation, economic study and programming, respectively. The results were interesting and essential for decision makers and investors to start implementing of these projects in reliable condition. The research is obtained through collection and study of the project's documents as well as recalculation to review conformity of the results with GIS data and the technical information of the bidders. In this paper, it is attempted to describe the result of the performed research by describing the five steps as an executive methodology, for preparing a feasible study of installing a 10 MW – solar farm project. The corresponding results of the research also help decision makers to start similar projects is explained in this paper as follows: selecting the best location for the concerned PV plant, reliable and safe conditions for investment and the required authorizations to start implementing the solar farm project in the concerned region, selecting suitable component to achieve the best possible performance for the plant, economic profit of the investment, proper programming to implement the project on time.Keywords: solar farm, solar energy, execution of PV power plant PV power plant
Procedia PDF Downloads 1652372 Synthesis of Magnetic Chitosan Beads and Its Cross-Linked Derivatives for Sorption of Zinc Ions from Water Samples of Yamuna and Hindon Rivers in India
Authors: Priti Rani, Rajni Johar, P. S. Jassal
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The magnetic chitosan beads (MCB) were synthesized using co-precipitation method and made to react with epichlorohydrin (ECH) to get the cross-linked derivative (ECH-MCB). The beads were characterized by FTIR, SEM, EDX, and TGA. It is found that zinc metal ion sorption efficiency of ECH-MCB is significantly higher than MCB. Various factors affecting the uptake behavior of metal ions, such as pH, adsorbent dosage, contact time, and temperature effects, were investigated. The adsorption parameters fitted well with Langmuir and Freundlich isotherms. The equilibrium parameter RL values support that the adsorption (0 < RL < 1) is favorable and spontaneous process. The thermodynamic parameters confirm that it is an endothermic reaction, which results in an increase in the randomness of adsorption process. The beads were regenerated using ethylene diamine tetraacetic acid (EDTA) for further use. These beads prove as promising materials for the removal of pollutants from industrial wastewater. Water samples from Yamuna and Hindon rivers were analysed for the detection of Zn (II) ions.Keywords: chitosan magnetic beads, EDTA, epichlorohydrin, removal efficiency
Procedia PDF Downloads 1422371 Impacts of Computer Assisted Instruction and Gender on High-Flyers Pre-Service Teachers' Attitude towards Agricultural Economics in Southwest Nigeria
Authors: Alice Morenike Olagunju, Olufemi A. Fakolade, Abiodun Ezekiel Adesina, Olufemi Akinloye Bolaji, Oriyomi Rabiu
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The use of computer-assisted instruction(CAI) has been suggested as a way out of the problem of Colleges of Education (CoE) in Southwest, Nigeria persistent high failure rate in and negative attitude towards Agricultural Economics (AE).The impacts of this are yet unascertained on high-flyers. This study, therefore, determined the impacts of CAI onhigh-flyers pre-service teachers’ attitude towards AE concepts in Southwest, Nigeria. The study adopted pretest-posttest, control group, quasi-experimental design. Six CoE with e-library facilities were purposively selected. Fourty-nine 200 level Agricultural education students offering introduction to AE course across the six CoE were participants. The participants were assigned to two groups (CAI, 22 and control, 27). Treatment lasted eight weeks. The AE Attitude Scale(r=0.80), Instructional guides and Teacher Performance Assessment Sheets were used for data collection. Data were analysed using t-test. The participants were 62.8% male with mean age of 22 years. Treatment had significant effects on high-flyers pre-service teachers’ attitude (t = 17.44; df = 47, p < .5). Participants in CAI ( =71.03) had higher post attitude mean score compared to those in control ( = 64.92) groups. Gender had no significant effect on attitude (t= 3.06; df= 47, p > .5). The computer assisted instructional mode enhanced students’ attitude towards Agricultural Economics concepts. Therefore, CAI should be adopted for improved attitude towards agricultural economics concepts among high-flyers pre-service teachers.Keywords: attitude towards agricultural economics concepts, colleges of education in southwest Nigeria, computer-assisted instruction, high-flyers pre-service teachers
Procedia PDF Downloads 2372370 Engineered Bio-Coal from Pressed Seed Cake for Removal of 2, 4, 6-Trichlorophenol with Parametric Optimization Using Box–Behnken Method
Authors: Harsha Nagar, Vineet Aniya, Alka Kumari, Satyavathi B.
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In the present study, engineered bio-coal was produced from pressed seed cake, which otherwise is non-edible in origin. The production process involves a slow pyrolysis wherein, based on the optimization of process parameters; a substantial reduction in H/C and O/C of 77% was achieved with respect to the original ratio of 1.67 and 0.8, respectively. The bio-coal, so the product was found to have a higher heating value of 29899 kJ/kg with surface area 17 m²/g and pore volume of 0.002 cc/g. The functional characterization of bio-coal and its subsequent modification was carried out to enhance its active sites, which were further used as an adsorbent material for removal of 2,4,6-Trichlorophenol (2,4,6-TCP) herbicide from the aqueous stream. The point of zero charge for the bio-coal was found to be pH < 3 where its surface is positively charged and attracts anions resulting in the maximum 2, 4, 6-TCP adsorption at pH 2.0. The parametric optimization of the adsorption process was studied based on the Box-Behken design with the desirability approach. The results showed optimum values of adsorption efficiency of 74.04% and uptake capacity of 118.336 mg/g for an initial metal concentration of 250 mg/l and particle size of 0.12 mm at pH 2.0 and 1 g/L of bio-coal loading. Negative Gibbs free energy change values indicated the feasibility of 2,4,6-TCP adsorption on biochar. Decreasing the ΔG values with the rise in temperature indicated high favourability at low temperatures. The equilibrium modeling results showed that both isotherms (Langmuir and Freundlich) accurately predicted the equilibrium data, which may be attributed to the different affinity of the functional groups of bio-coal for 2,4,6-TCP removal. The possible mechanism for 2,4,6-TCP adsorption is found to be physisorption (pore diffusion, p*_p electron donor-acceptor interaction, H-bonding, and van der Waals dispersion forces) and chemisorption (phenolic and amine groups chemical bonding) based on the kinetics data modeling.Keywords: engineered biocoal, 2, 4, 6-trichlorophenol, box behnken design, biosorption
Procedia PDF Downloads 1102369 Assessing Available Power from a Renewable Energy Source in the Southern Hemisphere using Anisotropic Model
Authors: Asowata Osamede, Trudy Sutherland
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The purpose of this paper is to assess the available power from a Renewable Energy Source (off-grid photovoltaic (PV) panel) in the Southern Hemisphere using anisotropic model. Direct solar radiation is the driving force in photovoltaics. In a basic PV panels in the Southern Hemisphere, Power conversion is eminent, and this is achieved by the PV cells converting solar energy into electrical energy. In this research, the results was determined for a 6 month period from September 2022 through February 2023. Preliminary results, which include Normal Probability plot, data analysis - R2 value, effective conversion-time per week and work-time per day, indicate a favorably comparison between the empirical results and the simulation results.Keywords: power-conversion, mathematical model, PV panels, DC-DC converters, direct solar radiation
Procedia PDF Downloads 732368 Solar-Thermal-Electric Stirling Engine-Powered System for Residential Units
Authors: Florian Misoc, Cyril Okhio, Joshua Tolbert, Nick Carlin, Thomas Ramey
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This project is focused on designing a Stirling engine system for a solar-thermal-electrical system that can supply electric power to a single residential unit. Since Stirling engines are heat engines operating any available heat source, is notable for its ability to generate clean and reliable energy without emissions. Due to the need of finding alternative energy sources, the Stirling engines are making a comeback with the recent technologies, which include thermal energy conservation during the heat transfer process. Recent reviews show mounting evidence and positive test results that Stirling engines are able to produce constant energy supply that ranges from 5kW to 20kW. Solar Power source is one of the many uses for Stirling engines. Using solar energy to operate Stirling engines is an idea considered by many researchers, due to the ease of adaptability of the Stirling engine. In this project, the Stirling engine developed was designed and tested to operate from biomass source of energy, i.e., wood pellets stove, during low solar radiation, with good results. A 20% efficiency of the engine was estimated, and 18% efficiency was measured, making it suitable and appropriate for residential applications. The effort reported was aimed at exploring parameters necessary to design, build and test a ‘Solar Powered Stirling Engine (SPSE)’ using Water (H₂O) as the Heat Transfer medium, with Nitrogen as the working gas that can reach or exceed an efficiency of 20%. The main objectives of this work consisted in: converting a V-twin cylinder air compressor into an alpha-type Stirling engine, construct a Solar Water Heater, by using an automotive radiator as the high-temperature reservoir for the Stirling engine, and an array of fixed mirrors that concentrate the solar radiation on the automotive radiator/high-temperature reservoir. The low-temperature reservoir is the surrounding air at ambient temperature. This work has determined that a low-cost system is sufficiently efficient and reliable. Off-the-shelf components have been used and estimates of the ability of the Engine final design to meet the electricity needs of small residence have been determined.Keywords: stirling engine, solar-thermal, power inverter, alternator
Procedia PDF Downloads 2692367 An Explanatory Study Approach Using Artificial Intelligence to Forecast Solar Energy Outcome
Authors: Agada N. Ihuoma, Nagata Yasunori
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Artificial intelligence (AI) techniques play a crucial role in predicting the expected energy outcome and its performance, analysis, modeling, and control of renewable energy. Renewable energy is becoming more popular for economic and environmental reasons. In the face of global energy consumption and increased depletion of most fossil fuels, the world is faced with the challenges of meeting the ever-increasing energy demands. Therefore, incorporating artificial intelligence to predict solar radiation outcomes from the intermittent sunlight is crucial to enable a balance between supply and demand of energy on loads, predict the performance and outcome of solar energy, enhance production planning and energy management, and ensure proper sizing of parameters when generating clean energy. However, one of the major problems of forecasting is the algorithms used to control, model, and predict performances of the energy systems, which are complicated and involves large computer power, differential equations, and time series. Also, having unreliable data (poor quality) for solar radiation over a geographical location as well as insufficient long series can be a bottleneck to actualization. To overcome these problems, this study employs the anaconda Navigator (Jupyter Notebook) for machine learning which can combine larger amounts of data with fast, iterative processing and intelligent algorithms allowing the software to learn automatically from patterns or features to predict the performance and outcome of Solar Energy which in turns enables the balance of supply and demand on loads as well as enhance production planning and energy management.Keywords: artificial Intelligence, backward elimination, linear regression, solar energy
Procedia PDF Downloads 1532366 Modelling and Optimization Analysis of Silicon/MgZnO-CBTSSe Tandem Solar Cells
Authors: Vallisree Sivathanu, Kumaraswamidhas Lakshmi Annamalai, Trupti Ranjan Lenka
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We report a tandem solar cell model with Silicon as the bottom cell absorber material and Cu₂BaSn(S, Se)₄(CBTSSe) as absorber material for the top cell. As a first step, the top and bottom cells were modelled and validated by comparison with the experiment. Once the individual cells are validated, then the tandem structure is modelled with Indium Tin Oxide(ITO) as conducting layer between the top and bottom cells. The tandem structure yielded better open circuit voltage and fill factor; however, the efficiency obtained is 7.01%. The top cell and the bottom cells are investigated with the help of electron-hole current density, photogeneration rate, and external quantum efficiency profiles. In order to minimize the various loss mechanisms in the tandem solar cell, the material parameters are optimized within experimentally achievable limits. Initially, the top cell optimization was carried out; then, the bottom cell is optimized for maximizing the light absorption, and upon minimizing the current and photon losses in the tandem structure, the maximum achievable efficiency is predicted to be 19.52%.Keywords: CBTSSe, silicon, tandem, solar cell, device modeling, current losses, photon losses
Procedia PDF Downloads 1032365 An Ab Initio Study of Delafossite Transparent Conductive Oxides Cu(In, Ga)O2 and Absorbers Films Cu(In, Ga)S2 in Solar-Cell
Authors: Mokdad Sakhri, Youcef Bouhadda
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Thin film chalcopyrite technology is thus nowadays a solid candidate for photovoltaic cells. The currently used window layer for the solar cell Cu(In,Ga)S2 is our interest point in this work. For this purpose, we have performed a first-principles study of structural, electronic and optical properties for both delafossite transparent conductive oxides Cu (In, Ga)O2 and absorbers films Cu(In,Ga)S2. The calculations have been carried out within the local density functional (LDA) and generalized gradient approximations (GGA) combined with the hubbard potential using norm-conserving pseudopotentials and a plane-wave basis with ABINIT code. We have found the energy gap is :1.6, 2.53, 3.6, 3.8 eV for CuInS2, CuGaS2, CuInO2 and CuGaO2 respectively. The results are in good agreement with experimental results.Keywords: ABINIT code, DFT, electronic and optical properties, solar-cell absorbers, delafossite transparent conductive oxides
Procedia PDF Downloads 5622364 Joining of Aluminum and Steel in Car Body Manufacturing
Authors: Mohammad Mahdi Mohammadi
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Zinc-coated steel sheets have been joined with aluminum samples in an overlapping as well as in a butt-joint configuration. A bi-metal-wire composed from aluminum and steel was used for additional welding experiments. An advantage of the laser-assisted bi-metal-wire welding is that the welding process is simplified since the primary joint between aluminium and steel exists already and laser welding occurs only between similar materials. FEM-simulations of the process were chosen to determine the ideal dimensions with respect to the formability of the bi-metal-wire. A prototype demonstrated the feasibility of the process.Keywords: car body, steel sheets, formability of bi-metal-wire, laser-assisted bi-metal-wire
Procedia PDF Downloads 5042363 Extraction of Nutraceutical Bioactive Compounds from the Native Algae Using Solvents with a Deep Natural Eutectic Point and Ultrasonic-assisted Extraction
Authors: Seyedeh Bahar Hashemi, Alireza Rahimi, Mehdi Arjmand
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Food is the source of energy and growth through the breakdown of its vital components and plays a vital role in human health and nutrition. Many natural compounds found in plant and animal materials play a special role in biological systems and the origin of many such compounds directly or indirectly is algae. Algae is an enormous source of polysaccharides and have gained much interest in human flourishing. In this study, algae biomass extraction is conducted using deep eutectic-based solvents (NADES) and Ultrasound-assisted extraction (UAE). The aim of this research is to extract bioactive compounds including total carotenoid, antioxidant activity, and polyphenolic contents. For this purpose, the influence of three important extraction parameters namely, biomass-to-solvent ratio, temperature, and time are studied with respect to their impact on the recovery of carotenoids, and phenolics, and on the extracts’ antioxidant activity. Here we employ the Response Surface Methodology for the process optimization. The influence of the independent parameters on each dependent is determined through Analysis of Variance. Our results show that Ultrasound-assisted extraction (UAE) for 50 min is the best extraction condition, and proline:lactic acid (1:1) and choline chloride:urea (1:2) extracts show the highest total phenolic contents (50.00 ± 0.70 mgGAE/gdw) and antioxidant activity [60.00 ± 1.70 mgTE/gdw, 70.00 ± 0.90 mgTE/gdw in 2.2-diphenyl-1-picrylhydrazyl (DPPH), and 2.2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)]. Our results confirm that the combination of UAE and NADES provides an excellent alternative to organic solvents for sustainable and green extraction and has huge potential for use in industrial applications involving the extraction of bioactive compounds from algae. This study is among the first attempts to optimize the effects of ultrasonic-assisted extraction, ultrasonic devices, and deep natural eutectic point and investigate their application in bioactive compounds extraction from algae. We also study the future perspective of ultrasound technology which helps to understand the complex mechanism of ultrasonic-assisted extraction and further guide its application in algae.Keywords: natural deep eutectic solvents, ultrasound-assisted extraction, algae, antioxidant activity, phenolic compounds, carotenoids
Procedia PDF Downloads 1632362 Wastewater Treatment by Modified Bentonite
Authors: Mecabih Zohra
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Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.Keywords: adsorption, bentonite, COD, wastewater
Procedia PDF Downloads 692361 Wastewater Treatment by Modified Bentonite
Authors: Mecabih Zohra
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Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.Keywords: adsorption, bentonite, COD, wastewater
Procedia PDF Downloads 732360 Noninvasive Continuous Glucose Monitoring Device Using a Photon-Assisted Tunneling Photodetector Based on a Quantum Metal-Oxide-Semiconductor
Authors: Wannakorn Sangthongngam, Melissa Huerta, Jaewoo Kim, Doyeon Kim
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Continuous glucose monitoring systems are essential for diabetics to avoid health complications but come at a costly price, especially when insurance does not fully cover the diabetic testing kits needed. This paper proposes a noninvasive continuous glucose monitoring system to provide an accessible, low-cost, and painless alternative method of accurate glucose measurements to help improve quality of life. Using a light source with a wavelength of 850nm illuminates the fingertip for the photodetector to detect the transmitted light. Utilizing SeeDevice’s photon-assisted tunneling photodetector (PAT-PD)-based QMOS™ sensor, fluctuations of voltage based on photon absorption in blood cells are comparable to traditional glucose measurements. The performance of the proposed method was validated using 4 test participants’ transmitted voltage readings compared with measurements obtained from the Accu-Chek glucometer. The proposed method was able to successfully measure concentrations from linear regression calculations.Keywords: continuous glucose monitoring, non-invasive continuous glucose monitoring, NIR, photon-assisted tunneling photodetector, QMOS™, wearable device
Procedia PDF Downloads 802359 Comparison between Torsional Ultrasonic Assisted Drilling and Conventional Drilling of Bone: An in vitro Study
Authors: Nikoo Soleimani
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Background: Reducing torque during bone drilling is one of the effective factors in reaching to an optimal drilling process. Methods: 15 bovine femurs were drilled in vitro with a drill bit with a diameter of 4 mm using two methods of torsional ultrasonic assisted drilling (T-UAD) and convent conventional drilling (CD) and the effects of changing the feed rate and rotational speed on the torque were compared in both methods. Results: There was no significant difference in the thrust force measured in both methods due to the direction of vibrations. Results showed that using T-UAD method for bone drilling at feed rates of 0.16, 0.24 and 0.32 mm/rev led for all rotational speeds to a decrease of at least 16.3% in torque compared to the CD method. Further, using T-UAD at rotational speeds of 355~1000 rpm with various feed rates resulted in a torque reduction of 16.3~50.5% compared to CD method. Conclusions: Reducing the feed rate and increasing the rotational speed, except for the rotational speed of 500 rpm and a feed rate of 0.32 mm/rev, resulted generally in torque reduction in both methods. However, T-UAD is a more effective and desirable option for bone drilling considering its significant torque reduction.Keywords: torsional ultrasonic assisted drilling, torque, bone drilling, rotational speed, feed rate
Procedia PDF Downloads 1482358 Electrochemical Studies of Some Schiff Bases on the Corrosion of Steel in H2SO4 Solution
Authors: Ahmed A. Farag, M. A. Hgazy
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The influence of three Schiff bases (SB-I, SB-II, and SB-III) on the corrosion of carbon steel in 0.5 M H2SO4 solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The inhibition efficiency increases with the concentration of the Schiff bases and follow the trend: SB-III > SB-II > SB-I. Tafel polarization measurements revealed that the three tested inhibitors function as anodic inhibitors. The thermodynamic parameters Kads and ΔGºads are calculated and discussed. The Langmuir isotherm equation was found to provide an accurate description of the adsorption behaviour of the investigated Schiff bases. Depending on the results, the inhibitive mechanism was proposed.Keywords: Schiff bases, corrosion inhibitors, EIS, adsorption
Procedia PDF Downloads 5312357 Effectiveness of the Resistance to Irradiance Test on Sunglasses Standards
Authors: Mauro Masili, Liliane Ventura
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It is still controversial in the literature the ultraviolet (UV) radiation effects on the ocular media, but the World Health Organization has established safe limits on the exposure of eyes to UV radiation based on reports in literature. Sunglasses play an important role in providing safety, and their lenses should provide adequate UV filters. Regarding UV protection for ocular media, the resistance-to-irradiance test for sunglasses under many national standards requires irradiating lenses for 50 uninterrupted hours with a 450 W solar simulator. This artificial aging test may provide a corresponding evaluation of exposure to the sun. Calculating the direct and diffuse solar irradiance at a vertical surface and the corresponding radiant exposure for the entire year, we compare the latter with the 50-hour radiant exposure of a 450 W xenon arc lamp from a solar simulator required by national standards. Our calculations indicate that this stress test is ineffective in its present form. We provide evidence of the need to re-evaluate the parameters of the tests to establish appropriate safe limits against UV radiation. This work is potentially significant for scientists and legislators in the field of sunglasses standards to improve the requirements of sunglasses quality and safety.Keywords: ISO 12312-1, solar simulator, sunglasses standards, UV protection
Procedia PDF Downloads 1902356 Preparation of Composite Alginate/Perlite Beads for Pb (II) Removal in Aqueous Solution
Authors: Hasan Türe, Kader Terzioglu, Evren Tunca
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Contamination of aqueous environment by heavy metal ions is a serious and complex problem, owing to their hazards to human being and ecological systems. The treatment methods utilized for removing metal ions from aqueous solution include membrane separation, ion exchange and chemical precipitation. However, these methods are limited by high operational cost. Recently, biobased beads are considered as promising biosorbent to remove heavy metal ions from water. The aim of present study was to characterize the alginate/perlite composite beads and to investigate the adsorption performance of obtained beads for removing Pb (II) from aqueous solution. Alginate beads were synthesized by ionic gelation methods and different amount of perlite (aljinate:perlite=1, 2, 3, 4, 5 wt./wt.) was incorporated into alginate beads. Samples were characterized by means of X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM). The effects of perlite level, the initial concentration of Pb (II), initial pH value of Pb(II) solution and effect of contact time on the adsorption capacity of beads were investigated by using batch method. XRD analysis indicated that perlite includes silicon or silicon and aluminum bearing crystalline phase. The diffraction pattern of perlite containing beads is similar to that of that perlite powder with reduced intensity. SEM analysis revealed that perlite was embedded into alginate polymer and SEM-EDX (Energy-Dispersive X-ray) showed that composite beads (aljinate:perlite=1) composed of C (41.93 wt.%,), O (43.64 wt.%), Na (10.20 wt.%), Al (0.74 wt.%), Si (2.72 wt.%) ve K (0.77 wt.%). According to TGA analysis, incorporation of perlite into beads significantly improved the thermal stability of the samples. Batch experiment indicated that optimum pH value for Pb (II) adsorption was found at pH=7 with 1 hour contact time. It was also found that the adsorption capacity of beads decreased with increases in perlite concentration. The results implied that alginate/perlite composite beads could be used as promising adsorbents for the removal of Pb (II) from wastewater. Acknowledgement: This study was supported by TUBITAK (Project No: 214Z146).Keywords: alginate, adsorption, beads, perlite
Procedia PDF Downloads 2802355 Adsorptive Desulfurization of Using Cu(I) – Y Zeolite via π-Complexation
Authors: Moshe Mello, Hilary Rutto, Tumisang Seodigeng, Itumeleng Kohitlhetse
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The accelerating requirement to reach 0% sulfur content in liquid fuels demand researchers to seek efficient alternative technologies to challenge the predicament. In this current study, the adsorption capabilities of modified Cu(I)-Y zeolite were tested for the removal of organosulfur compounds (OSC) present in tire pyrolytic oil (TPO). The π-complexation-based adsorbent was obtained by ion exchanging Y-zeolite with Cu+ cation using liquid phase ion exchange (LPIE). Preparation of the adsorbent involved firstly ion exchange between Na-Y zeolite with a Cu(NO₃)₂ aqueous solution of 0.5M for 48 hours followed by reduction of Cu²⁺ to Cu+. Fixed-bed breakthrough studies for TPO in comparison with model diesel comprising of sulfur compounds such as thiophene, benzothiophenes (BT), and dibenzothiophenes (DBT) showed that modified Cu(I)-Y zeolite is an effective adsorbent for removal of OSC in liquid fuels. The effect of operating conditions such as adsorbent dosage and reaction time were studied to optimize the adsorptive desulfurization process. For model diesel fuel, the selectivity for adsorption of sulfur compounds followed the order DBT> BT> Thiophene. The Cu(I)-Y zeolite is fully regeneratable and this is achieved by a simple procedure of blowing the adsorbent with air at 350 °C, followed by reactivation at 450 °C in a rich helium surrounding.Keywords: adsorption, desulfurization, TPO, zeolite
Procedia PDF Downloads 1042354 Empirical Analysis of the Effect of Cloud Movement in a Basic Off-Grid Photovoltaic System: Case Study Using Transient Response of DC-DC Converters
Authors: Asowata Osamede, Christo Pienaar, Johan Bekker
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Mismatch in electrical energy (power) or outage from commercial providers, in general, does not promote development to the public and private sector, these basically limit the development of industries. The necessity for a well-structured photovoltaic (PV) system is of importance for an efficient and cost-effective monitoring system. The major renewable energy potential on earth is provided from solar radiation and solar photovoltaics (PV) are considered a promising technological solution to support the global transformation to a low-carbon economy and reduction on the dependence on fossil fuels. Solar arrays which consist of various PV module should be operated at the maximum power point in order to reduce the overall cost of the system. So power regulation and conditioning circuits should be incorporated in the set-up of a PV system. Power regulation circuits used in PV systems include maximum power point trackers, DC-DC converters and solar chargers. Inappropriate choice of power conditioning device in a basic off-grid PV system can attribute to power loss, hence the need for a right choice of power conditioning device to be coupled with the system of the essence. This paper presents the design and implementation of a power conditioning devices in order to improve the overall yield from the availability of solar energy and the system’s total efficiency. The power conditioning devices taken into consideration in the project includes the Buck and Boost DC-DC converters as well as solar chargers with MPPT. A logging interface circuit (LIC) is designed and employed into the system. The LIC is designed on a printed circuit board. It basically has DC current signalling sensors, specifically the LTS 6-NP. The LIC is consequently required to program the voltages in the system (these include the PV voltage and the power conditioning device voltage). The voltage is structured in such a way that it can be accommodated by the data logger. Preliminary results which include availability of power as well as power loss in the system and efficiency will be presented and this would be used to draw the final conclusion.Keywords: tilt and orientation angles, solar chargers, PV panels, storage devices, direct solar radiation
Procedia PDF Downloads 1282353 Application of Functionalized Magnetic Particles as Demulsifier for Oil‐in‐Water Emulsions
Authors: Hamideh Hamedi, Nima Rezaei, Sohrab Zendehboudi
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Separating emulsified oil contaminations from waste- or produced water is of interest to various industries. Magnetic particles (MPs) application for separating dispersed and emulsified oil from wastewater is becoming more popular. Stabilization of MPs is required through developing a coating layer on their surfaces to prevent their agglomeration and enhance their dispersibility. In this research, we study the effects of coating material, size, and concentration of iron oxide MPs on oil separation efficiency, using oil adsorption capacity measurements. We functionalize both micro-and nanoparticles of Fe3O4 using sodium dodecyl sulfate (SDS) as an anionic surfactant, cetyltrimethylammonium bromide (CTAB) as a cationic surfactant, and stearic acid (SA). The chemical structures and morphologies of these particles are characterized using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Energy Dispersive X-ray (EDX). The oil-water separation results indicate that a low dosage of the coated magnetic nanoparticle with CTAB (0.5 g/L MNP-CTAB) results the highest oil adsorption capacity (nearly 100%) for 1000 ppm dodecane-in-water emulsion, containing ultra-small droplets (250–300 nm). While separation efficiency of the same dosage of bare MNPs is around 57.5%. Demulsification results of magnetic microparticles (MMPs) also reveal that the functionalizing particles with CTAB increase oil removal efficiency from 86.3% for bare MMP to 92% for MMP-CTAB. Comparing the results of different coating materials implies that the major interaction reaction is an electrostatic attraction between negatively charged oil droplets and positively charged MNP-CTAB and MMP-CTAB. Furthermore, the synthesized nanoparticles could be recycled and reused; after ten cycles the oil adsorption capacity slightly decreases to near 95%. In conclusion, functionalized magnetic particles with high oil separation efficiency could be used effectively in treatment of oily wastewater. Finally, optimization of the adsorption process is required by considering the effective system variables, and fluid properties.Keywords: oily wastewater treatment, emulsions, oil-water separation, adsorption, magnetic nanoparticles
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