Search results for: operating temperature

Authors: Umair Ahmed, Muhammad Bin Irfan

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This study focuses on designing and optimization of an alkaline water electrolyser for the production of green hydrogen. The aim is to enhance the durability and efficiency of this technology while simultaneously reducing the cost associated with the production of green hydrogen. The experimental results obtained from the alkaline water electrolyser are compared with simulated results using Aspen Plus software, allowing a comprehensive analysis and evaluation. To achieve the aforementioned goals, several design and operational parameters are investigated. The electrode material, electrolyte concentration, and operating conditions are carefully selected to maximize the efficiency and durability of the electrolyser. Additionally, cost-effective materials and manufacturing techniques are explored to decrease the overall production cost of green hydrogen. The experimental setup includes a carefully designed alkaline water electrolyser, where various performance parameters (such as hydrogen production rate, current density, and voltage) are measured. These experimental results are then compared with simulated data obtained using Aspen Plus software. The simulation model is developed based on fundamental principles and validated against the experimental data. The comparison between experimental and simulated results provides valuable insight into the performance of an alkaline water electrolyser. It helps to identify the areas where improvements can be made, both in terms of design and operation, to enhance the durability and efficiency of the system. Furthermore, the simulation results allow cost analysis providing an estimate of the overall production cost of green hydrogen. This study aims to develop a comprehensive understanding of alkaline water electrolysis technology. The findings of this research can contribute to the development of more efficient and durable electrolyser technology while reducing the cost associated with this technology. Ultimately, these advancements can pave the way for a more sustainable and economically viable hydrogen economy.

Keywords: sustainable development, green energy, green hydrogen, electrolysis technology

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Authors: A. Kourou, A. Ioakeimidou, E. Bafa, C. Fassoulas, M. Panoutsopoulou

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The role of volunteers in disaster management is of decisive importance and the need of their involvement is well recognized, both for prevention measures and for disaster management. During major catastrophes, whereas professional personnel are outsourced, the role of volunteers is crucial. In Greece experience has shown that various groups operating in the civil protection mechanism like local administration staff or volunteers, in many cases do not have the necessary knowledge and information on best practices to act against natural disasters. One of the major problems is the lack of volunteers’ education and training. In the above given framework, this paper presents the results of a survey aimed to identify the level of education and preparedness of civil protection volunteers in Greece. Furthermore, the implementation of earthquake protection measures at individual, family and working level, are explored. More specifically, the survey questionnaire investigates issues regarding pre-earthquake protection actions, appropriate attitudes and behaviors during an earthquake and existence of contingency plans in the workplace. The questionnaires were administered to citizens from different regions of the country and who attend the civil protection training program: “Protect Myself and Others”. A closed-form questionnaire was developed for the survey, which contained questions regarding the following: a) knowledge of self-protective actions; b) existence of emergency planning at home; c) existence of emergency planning at workplace (hazard mitigation actions, evacuation plan, and performance of drills); and, d) respondents` perception about their level of earthquake preparedness. The results revealed a serious lack of knowledge and preparedness among respondents. Taking into consideration the aforementioned gap and in order to raise awareness and improve preparedness and effective response of volunteers acting in civil protection, the EVANDE project was submitted and approved by the European Commission (EC). The aim of that project is to educate and train civil protection volunteers on the most serious natural disasters, such as forest fires, floods, and earthquakes, and thus, increase their performance.

Keywords: civil protection, earthquake, preparedness, volunteers

Procedia PDF Downloads 246

Authors: A. M. Ahmed, Mona A. Darwish

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Removal of Ni++ ions from aqueous solution by sorption ontoNano-bentonite was investigated. Experiments were carried out as a function amount of Nano-bentonite, pH, concentration of metal, constant time, agitation speed and temperature. The adsorption parameter of metal ions followed the Langmuir Freundlich adsorption isotherm were applied to analyze adsorption data. The adsorption process has fit pseudo-second order kinetic models. Thermodynamics parameters e.g.ΔG*, ΔS °and ΔH ° of adsorption process have also been calculated and the sorption process was found to be endothermic. The adsorption process has fit pseudo-second order kinetic models. Langmuir and Freundich adsorption isotherm models were applied to analyze adsorption data and both were found to be applicable to the adsorption process. Thermodynamic parameters, e.g., ∆G °, ∆S ° and ∆H ° of the on-going adsorption process have also been calculated and the sorption process was found to be endothermic. Finally, it can be seen that Bentonite was found to be more effective for the removal of Ni (II) same with some experimental conditions.

Keywords: waste water, nickel, bentonite, adsorption

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Authors: Hakim T. Kadhim, Faris A. Jabbar, Aldo Rona, Audrius Bagdanaviciu

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Computer-based optimization techniques can be employed to improve the efficiency of energy conversions processes, including reducing the aerodynamic loss in a thermal power plant turbomachine. In this paper, towards mitigating secondary flow losses, a design optimization workflow is implemented for the casing geometry of a 1.5 stage axial flow turbine that improves the turbine isentropic efficiency. The improved turbine is used in an open thermodynamic gas cycle with regeneration and cogeneration. Performance estimates are obtained by the commercial software Cycle – Tempo. Design and off design conditions are considered as well as variations in inlet air temperature. Reductions in both the natural gas specific fuel consumption and in CO₂ emissions are predicted by using the gas turbine cycle fitted with the new casing design. These gains are attractive towards enhancing the competitiveness and reducing the environmental impact of thermal power plant.

Keywords: axial flow turbine, computational fluid dynamics, gas turbine power plant, optimization

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Authors: Claudia Camargo Wilson, Enrique Javier de la Vega Bustillos, Jesús Everardo Olguín Tiznado, Juan Andrés López Barreras, Sandra K. Enriquez

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This study focuses on the application of sensory thermography, as a non-invasive method to evaluate the musculoskeletal injuries that industry workers performing Highly Repetitive Movements (HRM) may acquire. It was made at a wireless company having the target of analyze temperatures in worker’s wrists, elbows and shoulders in workstations during their activities, this thru sensorial thermography with the goal of detecting maximum temperatures (Tmax) that could indicate possible injuries. The tests were applied during 3 hours for only 2 workers that work in workstations where there’s been the highest index of injuries and accidents. We were made comparisons for each part of the body that were study for both because of the similitude between the activities of the workstations; they were requiring both an immediate evaluation. The Tmax was recorder during the test of the worker 2, in the left wrist, reaching a temperature of 35.088ºC and with a maximum increase of 1.856°C.

Keywords: thermography, maximum temperaturas (Tmax), highly repetitive movements (HRM), operator

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Authors: Gampel Alexander, Mazzuchi Thomas, Sarkani Shahram

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The cybersecurity landscape is constantly evolving, and organizations must adapt to the changing threat environment to protect their assets. The implementation of the NIST Risk Management Framework (RMF) has become critical in ensuring the security and safety of industrial control and automation systems. However, cybersecurity professionals are facing challenges in implementing RMF, leading to systems operating without authorization and being non-compliant with regulations. The current approach to RMF implementation based on business practices is limited and insufficient, leaving organizations vulnerable to cyberattacks resulting in the loss of personal consumer data and critical infrastructure details. To address these challenges, this research proposes a Model-Based Systems Engineering (MBSE) approach to implementing cybersecurity controls and assessing risk through the RMF process. The study emphasizes the need to shift to a modeling approach, which can streamline the RMF process and eliminate bloated structures that make it difficult to receive an Authorization-To-Operate (ATO). The study focuses on the practical application of MBSE in industrial control and automation systems to improve the security and safety of operations. It is concluded that MBSE can be used to solve the implementation challenges of the NIST RMF process and improve the security of industrial control and automation systems. The research suggests that MBSE provides a more effective and efficient method for implementing cybersecurity controls and assessing risk through the RMF process. The future work for this research involves exploring the broader applicability of MBSE in different industries and domains. The study suggests that the MBSE approach can be applied to other domains beyond industrial control and automation systems.

Keywords: authorization-to-operate (ATO), industrial control systems (ICS), model-based system’s engineering (MBSE), risk management framework (RMF)

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Authors: Magdalena Jabłońska-Czapla

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The work allowed gaining knowledge about redox and speciation changes of As, Cr, and Sb ionic forms in Klodnica River water. This kind of studies never has been conducted in this region of Poland. In study optimized and validated previously HPLC-ICP-MS methods for determination of As, Sb and Cr was used. Separation step was done using high-performance liquid chromatograph equipped with ion-exchange column followed by ICP-MS spectrometer detector. Preliminary studies included determination of the total concentration of As, Sb and Cr, pH, Eh, temperature and conductivity of the water samples. The study was conducted monthly from March to August 2014, at six points on the Klodnica River. The results indicate that exceeded at acceptable concentration of total Cr and Sb was observed in Klodnica River and we should qualify Klodnica River waters below the second purity class. In Klodnica River waters dominates oxidized antimony and arsenic forms, as well as the two forms of chromium Cr(VI) and Cr(III). Studies have also shown the methyl derivative of arsenic's presence.

Keywords: antimony, arsenic, chromium, HPLC-ICP-MS, river water, speciation

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Authors: Khawaja A. Wahaj Wani, Aykut Erkal

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Pakistan's construction industry, a key player in economic development, has experienced remarkable growth. However, the surge in activities has been accompanied by dangerous working conditions, attributed to legislative gaps and flaws. Unhealthy construction practices, uncertain site conditions, and hazardous environments contribute to a concerning rate of injuries and fatalities. The principal aim of this research study is to undertake a thorough evaluation based on the assessment of the current situation of Health & Safety policies and the surveys performed by stakeholders of Pakistan with the aim of providing solution-centric methodologies for the enforcement of health and safety regulations within construction companies operating on project sites. Recognizing the pivotal role that the construction industry plays in bolstering a nation's economy, it is imperative to address the pressing need for heightened awareness among site engineers and laborers. The study adopts a robust approach, utilizing questionnaire surveys and interviews. As an exclusive investigative study, it encompasses all stakeholders: clients, consultants, contractors, and subcontractors. Targeting PEC-registered companies. Safety performance was assessed through the examination of sixty safety procedures using SPSS-18. A high Cronbach's alpha value of 0.958 ensures data reliability, and non-parametric tests were employed due to the non-normal distribution of data. The safety performance evaluation revealed significant insights. "Using Hoists and Cranes" and "Precautionary Measures (Shoring and Excavation)" exhibited commendable safety levels. Conversely, "Trainings on Safety" displayed a lower safety performance, alongside areas such as "Safety in Contract Documentation," "Meetings for Safety," and "Worker Participation," indicating room for improvement. These findings provide stakeholders with a detailed understanding of current safety measures within Pakistan's construction industry.

Keywords: construction industry, health and safety regulations, Pakistan, risk management

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Authors: T. Wejrzanowski, M. Grybczuk, E. Tymicki, K. J. Kurzydlowski

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In the present study, numerical simulations of heat and mass transfer in Physical Vapor Transport reactor during silicon carbide single crystal growth are addressed. Silicon carbide is a wide bandgap material with unique properties making it highly applicable for high power electronics applications. Because of high manufacturing costs improvements of SiC production process are required. In this study, numerical simulations were used as a tool of process optimization. Computer modeling allows for cost and time effective analysis of processes occurring during SiC single crystal growth and provides essential information needed for improvement of the process. Quantitative relationship between process conditions, such as temperature or pressure, and crystal growth rate and shape of crystallization front have been studied and verified using experimental data. Basing on modeling results, several process improvements were proposed and implemented.

Keywords: Finite Volume Method, semiconductors, Physica Vapor Transport, silicon carbide

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Authors: Rifda Naufalin, Nurul Latifasari, Siti Nuryanti, Muna Ridha Hanifah

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Kecombrang is a Zingiberaceae plant which has antioxidant properties. The high antioxidant content in kecombrang flowers has the potential to be processed as a functional beverage raw material so that it can be used as an ingredient in making herbal teas. The purpose of this study was to determine the chemical components, physicochemistry, antioxidant activity and sensory characteristics of kecombrang tea. The research methodology was carried out by using a completely randomized design with processing factors of kecombrang tea namely blanching and non-blanching, fermentation and non-fermentation, and the optimal time for drying kecombrang tea. The best treatment combination based on the effective index method is the treatment of the blanching process followed by drying at a temperature of 50ᵒC until the 2% moisture content can produce kecombrang tea with a total phenol content of 5.95 mg Tannic Acid Equivalent (TAE) / gram db, total flavonoid 3%, pH 4.5, and antioxidant activity 82.95%, red color, distinctive aroma of tea, fresh taste, and preferred by panelists.

Keywords: kecombrang tea, blanching, fermentation, total phenol, and antioxidant activity

Procedia PDF Downloads 151

Authors: N. Ouslimani, M. T. Abadlia, S. Yakoub, F. Tebbani

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Water has always been synonymous with life and growth. Blue gold is first essential to the survival of the human being whose body consists of more than 65% with the development of industrialization and consumption patterns; volumes of wastewater discharges have increased considerably whether industrial or domestic, waste water must be purified before discharge. Treatment, therefore, aims to reduce the pollution load which contain. The resources in Algeria are limited and unevenly distributed. Thus, to meet all the water needs of the country and to preserve the waters of good quality drinking water supply, one solution would be to use them according to their quality and to irrigate crops for the food or be directed to the irrigation of green areas or sports complex. The purification performance of this STEP has been established since the pH analyzed pollution criteria (7.36) and temperature (16°C), MES (10 mg / l), electrical conductivity (1122 / µs / cm), DBO5 (6mg / l), DCO (15mg / l) meet the discharge standards. Arguably the purified water discharged out of the boumerdes STEP comply with Algerian regulations and can be reused in agriculture. COD biodegradability of the coefficient / BOD5 is 2.5 (less than 3) indicates that of the effluent are biodegradable hence their urban origin.

Keywords: irrigation, recovery, treated, wastewater

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Authors: Tugba Yilmaz Aydin, Ergun Guntekin, Murat Aydin

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Effects of heat treatment on the elastic constants of cedar wood (Cedrus libani) were investigated. Specimens were exposed to heat under atmospheric pressure at four different temperatures (120, 150, 180, 210 °C) and three different time levels (2, 5, 8 hours). Three Young’s modulus (EL, ER, ET) and six Poisson ratios (μLR, μLT, μRL, μRT, μTL, μTR) were determined from compression test using bi-axial extensometer at constant moisture content (12 %). Three shear modulus were determined using ultrasound. Six shear wave velocities propagating along the principal axes of anisotropy were measured using EPOCH 650 ultrasonic flaw detector with 1 MHz transverse transducers. The properties of the samples tested were significantly affected by heat treatment by different degree. As a result, softer treatments yielded some amount of increase in Young modulus and shear modulus values, but increase of time and temperature resulted in significant decrease for both values. Poisson ratios seemed insensitive to heat treatment.

Keywords: cedar wood, elastic constants, heat treatment, ultrasound

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Authors: Kahina Bedda, Boudjema Hamada

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Environmental regulations have been introduced in many countries around the world to reduce the sulfur content of diesel fuel to ultra low levels with the intention of lowering diesel engine’s harmful exhaust emissions and improving air quality. Removal of sulfur containing compounds from diesel feedstocks to produce ultra low sulfur diesel fuel by extraction with selective solvents has received increasing attention in recent years. This is because the sulfur extraction technologies compared to the hydrotreating processes could reduce the cost of desulfurization substantially since they do not demand hydrogen, and are carried out at atmospheric pressure. In this work, the desulfurization of distillate gasoil by liquid-liquid extraction with N, N-dimethylformamide was investigated. This fraction was recovered from a mixture of Hassi Messaoud crude oils and Hassi R'Mel gas-condensate in Algiers refinery. The sulfur content of this cut is 281 ppm. Experiments were performed in six-stage with a ratio of solvent:feed equal to 3:1. The effect of the extraction temperature was investigated in the interval 30 ÷ 110°C. At 110°C the yield of refined gas oil was 82% and its sulfur content was 69 ppm.

Keywords: desulfurization, gasoil, N, N-dimethylformamide, sulfur content

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Authors: P. C. Okafor, A. J. Ekpunobi

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Mn doped copper sulphide (CuS:Mn) nano-films were deposited on indiums coated tin oxide (ITO) glass substrates using electrodeposition method. Electrodeposition was carried out using bath of PH = 3 at room temperature. Other depositions parameters such as deposition time (DT) are kept constant while Mn doping was varied from 3% to 23%. Absorption spectra of CuS:Mn films was obtained by using JENWAY 6405 UV-VIS -spectrophotometer. Optical band gap (E_g ), optical conductivity (σo) and electrical conductivity (σe) of CuS:Mn films were determined using absorption spectra and appropriate formula. The effect of Mn doping % on these properties were investigated. Results show that film thickness (t) for the 13.27 nm to 18.49 nm; absorption coefficient (α) from 0.90 x 1011 to 1.50 x 1011 optical band gap from 2.29eV to 2.35 eV; optical conductivity from 1.70 x 1013 and electrical conductivity from 160 millions to 154 millions. Possible applications of such films for solar cells fabrication and optoelectronic devices applications were also discussed.

Keywords: copper sulphide (CuS), Manganese (Mn) doping, electrodeposition, optical band gap, optical conductivity, electrical conductivity

Procedia PDF Downloads 725

Authors: Aptullah Karakas, Murat Baydogan

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The hot dip aluminizing (HDA) process involves immersing a metallic substrate into a molten aluminum bath for several minutes, and removed from the bath and cooled down to room temperature. After the HDA process, various aluminide layers are formed as a result of interdiffusion between the substrate and the molten aluminum and between the aluminide layers. In order to form a uniform aluminide layer, the specimen must be covered and wet well by the molten aluminum. Surface roughness plays an important role in wettability, and thus, surface preparation is an important stage in determining the final surface roughness. In this study, different roughness values were achieved by grinding the surface with emery papers as 180, 320 and 600 grids. After the surface preparation, the HDA process was performed in a molten Al-Si bath at 700 ᴼC for 10 minutes. After the HDA process, a microstructural examination of the coating was carried out to evaluate the uniformity of the coating and adhesion between the substrate and the coating. According to the results, the best adhesion at the interface was observed on the specimen, which was prepared by 320 grid emery paper having a mean surface roughness (Ra) of 0.097 µm.

Keywords: hot-dip aluminizing, microstructure, surface roughness, coating

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Authors: M. Heidari, A. Safekordi, A. Zamaniyan, E. Ganji Babakhani, M. Amanipour

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Perovskite-type membrane Ba_0.5Sr_0.5Ce_0.9Y_0.1O_3-δ (BSCY) was successfully synthesized by liquid citrate method. The hydrogen permeation and stability of BSCY perovskite-type membranes were studied at high temperatures. The phase structure of the powder was characterized by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was used to characterize microstructures of the membrane sintered under various conditions. SEM results showed that increasing in sintering temperature, formed dense membrane with clear grains. XRD results for BSCY membrane that sintered in 1150 °C indicated single phase perovskite structure with orthorhombic configuration, and SEM results showed dense structure with clear grain size which is suitable for permeation tests. Partial substitution of Sr with Ba in SCY structure improved the hydrogen permeation flux through the membrane due to the larger ionic radius of Ba²⁺. BSCY membrane shows high hydrogen permeation flux of 1.6 ml/min.cm² at 900 °C and partial pressure of 0.6.

Keywords: hydrogen separation, perovskite, proton conducting membrane.

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Authors: Bum Yean Cho, Heung-Youl Kim, Ki-Seok Kwon, Kang-Su Kim

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In this study, a full-scale test and analysis (numerical analysis) of fire resistance performance of bare CFT column on which slot was used instead of existing welding method to connect the steel pipe on the concrete-filled tube were conducted. Welded CFT column is known to be vulnerable to high or low temperature because of low brittleness of welding part. As a result of a fire resistance performance test of slot CFT column after removing the welding part and fixing it by a slot which was folded into the tube, slot type CFT column indicated the improved fire resistance performance than welded CFT column by 28% or more. And as a result of conducting finite element analysis of slot type column using ABAQUS, analysis result proved the reliability of the test result in predicting the fire behavior and fire resistance hour.

Keywords: CFT (concrete-filled tube) column, fire resistance performance, slot, weld

Procedia PDF Downloads 188

Authors: Kuen-Ming Shu, Jyun-Wei Chen

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Encapsulated O-rings are specifically designed to address the problem of sealing the most hostile chemicals and extreme temperature applications. Ultrasonic vibration hot embossing and ultrasonic welding techniques provide a fast and reliable method to fabricate encapsulated O-ring. This paper performs the design and analysis method of the acoustic horns with double extrusion to process tube double side flange simultaneously. The paper deals with study through Finite Element Method (FEM) of ultrasonic stepped horn used to process a capsulated O-ring, the theoretical dimensions of horns, and their natural frequencies and amplitudes are obtained through the simulations of COMOSOL software. Furthermore, real horns were fabricated, tested and verified to proof the practical utility of these horns.

Keywords: encapsulated O-rings, ultrasonic vibration hot embossing, flange making, acoustic horn, finite element analysis

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Authors: Saad M. Alshehri, Tansir Ahamad

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Thiourea-Formaldehyde Pre-Polymer (TUF) was prepared by the reaction thiourea and formaldehyde in basic medium and used as a coating materials for magnetite Fe3O4. The synthesized polymer coated microspheres (TUF@Fe3O4) was characterized using FTIR, TGA SEM and TEM. Its BET surface area was up to 1680 m2 g_1. The adsorption capacity of this ACF product was evaluated in its adsorption of Methylene Blue (MB) in water under different pH values and different temperature. We found that the adsorption process was well described both by the Langmuir and Freundlich isotherm model. The kinetic processes of MB adsorption onto TUF@Fe3O4 were described in order to provide a more clear interpretation of the adsorption rate and uptake mechanism. The overall kinetic data was acceptably explained by a pseudo second-order rate model. Evaluated ∆Go and ∆Ho specify the spontaneous and exothermic nature of the reaction. The adsorption takes place with a decrease in entropy (∆So is negative). The monolayer capacity for MB was up to 450 mg g_1 and was one of the highest among similar polymeric products. It was due to its large BET surface area.

Keywords: TGA, FTIR, magentite, thiourea formaldehyde resin, methylene blue, adsorption

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Authors: Miraz Hafiz Rossy

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As part of planning to address shortfalls in fresh water supply for the world, Sea water can be a huge source of fresh water. But Desalinating sea water to get fresh water could require a lots of fossil fuels. To save the fossil fuel in terms of save the green world but meet the up growing need for fresh water, a very useful but energy efficient method needs to be introduced. Vacuum desalination of sea water using only the Renewable energy can be an effective solution to this issue. Taking advantage of sensitivity of water's boiling point to air pressure a vacuum desalination water treatment plant can be designed which would only use sea water as feed water and solar energy as fuel to produce fresh drinking water. The study indicates that reducing the air pressure to a certain value water can be boiled at very low temperature. Using solar energy to provide the condensation and the vacuum creation would be very useful and efficient. Compared to existing resources, desalination is considered to be expensive, but using only renewable energy the cost can be reduced significantly. Despite its very few drawbacks, it can be considered a possible solution to the world's fresh water shortages.

Keywords: desalination, scarcity of fresh water, water purification, water treatment

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Authors: Burcu Kiren, Alattin CAkan, Nezihe Ayas

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Hydrogen will be arguably the best fuel in the future as it is the most abundant element in the universe. Hydrogen, as a fuel, is notably environmentally benign, sustainable and has high energy content compared to other sources of energy. It can be generated from both conventional and renewable sources. The hydrolysis reaction of metal hydrides provides an option for hydrogen production in the presence of a catalyst. In this study, Ni/dolomite catalyst was synthesized by the wet impregnation method for hydrogen production by hydrolysis reaction of sodium borohydride (NaBH4). Besides, the synthesized catalysts characterizations were examined by means of thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer –Emmett – Teller (BET) and scanning electron microscopy (SEM). The influence of reaction temperature (25-75 °C), reaction time (15-60 min.), amount of catalyst (50-250 mg) and active metal loading ratio (20,30,40 wt.%) were investigated. The catalyst prepared with 30 wt.% Ni was noted as the most suitable catalyst, achieving of 35.18% H₂ and hydrogen production rate of 19.23 mL/gcat.min at 25 °C at reaction conditions of 5 mL of 0.25 M NaOH and 100 mg NaBH₄, 100 mg Ni/dolomite.

Keywords: sodium borohydride, hydrolysis, catalyst, Ni/dolomite, hydrogen

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Authors: Nikolaos Reppas, Yilin Gui

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A dual-porosity finite element-code will be presented for the stability analysis of the wellbore during CO₂ injection. An elastoplastic damage response will be considered to the model. The Finite Element Method (FEM) will be validated using experimental results from literature or from experiments that are planned to be undertaken at Newcastle University. The main target of the research paper is to present a constitutive model that can help industries to safely store CO₂ in geological rock formations and forecast any changes on the surrounding rock of the wellbore. The fully coupled elastoplastic damage Thermo-Hydraulic-Mechanical (THM) model will determine the pressure and temperature of the injected CO₂ as well as the size of the radius of the wellbore that can make the Carbon Capture and Storage (CCS) procedure more efficient.

Keywords: carbon capture and storage, Wellbore stability, elastoplastic damage response for rock, constitutive THM model, fully coupled thermo-hydraulic-mechanical model

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Authors: Bandreddy Anand Babu, Srinivasa Rao Mandadi, C. Pradeep Reddy, N. Ramesh Babu

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In this paper quickly illustrate the correlation investigation of Auto-Regressive Integrated Moving and Average (ARIMA) and daptive Network Based Fuzzy Inference System (ANFIS) models done by climate estimating. The climate determining is taken from University of Waterloo. The information is taken as Relative Humidity, Ambient Air Temperature, Barometric Pressure and Wind Direction utilized within this paper. The paper is carried out by analyzing the exhibitions are seen by demonstrating of ARIMA and ANIFIS model like with Sum of average of errors. Versatile Network Based Fuzzy Inference System (ANFIS) demonstrating is carried out by Mat lab programming and Auto-Regressive Integrated Moving and Average (ARIMA) displaying is produced by utilizing XLSTAT programming. ANFIS is carried out in Fuzzy Logic Toolbox in Mat Lab programming.

Keywords: ARIMA, ANFIS, fuzzy surmising tool stash, weather forecasting, MATLAB

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Authors: Yichao Liu, Peter Fransson, Julian Heidecke, Jonas Wallin, Joacim Rockloev

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Dengue, a mosquito-borne viral disease, poses a significant public health challenge in endemic tropical or subtropical countries, including Sri Lanka. To reveal insights into the complexity of the dynamics of this disease and study the drivers, a comprehensive model capable of both robust forecasting and insightful inference of drivers while capturing the co-circulating of several virus strains is essential. However, existing studies mostly focus on only one aspect at a time and do not integrate and carry insights across the siloed approach. While mechanistic models are developed to capture immunity dynamics, they are often oversimplified and lack integration of all the diverse drivers of disease transmission. On the other hand, purely data-driven methods lack constraints imposed by immuno-epidemiological processes, making them prone to overfitting and inference bias. This research presents a hybrid model that combines machine learning techniques with mechanistic modelling to overcome the limitations of existing approaches. Leveraging eight years of newly reported dengue case data, along with socioeconomic factors, such as human mobility, weekly climate data from 2011 to 2018, genetic data detecting the introduction and presence of new strains, and estimates of seropositivity for different districts in Sri Lanka, we derive a data-driven vector (SEI) to human (SEIR) model across 16 regions in Sri Lanka at the weekly time scale. By conducting ablation studies, the lag effects allowing delays up to 12 weeks of time-varying climate factors were determined. The model demonstrates superior predictive performance over a pure machine learning approach when considering lead times of 5 and 10 weeks on data withheld from model fitting. It further reveals several interesting interpretable findings of drivers while adjusting for the dynamics and influences of immunity and introduction of a new strain. The study uncovers strong influences of socioeconomic variables: population density, mobility, household income and rural vs. urban population. The study reveals substantial sensitivity to the diurnal temperature range and precipitation, while mean temperature and humidity appear less important in the study location. Additionally, the model indicated sensitivity to vegetation index, both max and average. Predictions on testing data reveal high model accuracy. Overall, this study advances the knowledge of dengue transmission in Sri Lanka and demonstrates the importance of incorporating hybrid modelling techniques to use biologically informed model structures with flexible data-driven estimates of model parameters. The findings show the potential to both inference of drivers in situations of complex disease dynamics and robust forecasting models.

Keywords: compartmental model, climate, dengue, machine learning, social-economic

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Authors: James Ladzekpo

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Background: The urgent need to identify new pharmacological targets for diabetes treatment and prevention has been amplified by the disease's extensive impact on individuals and healthcare systems. A deeper insight into the biological underpinnings of diabetes is crucial for the creation of therapeutic strategies aimed at these biological processes. Current predictive models based on genetic variations fall short of accurately forecasting diabetes. Objectives: Our study aims to pinpoint key epigenetic factors that predispose individuals to diabetes. These factors will inform the development of an advanced predictive model that estimates diabetes risk from genetic profiles, utilizing state-of-the-art statistical and data mining methods. Methodology: We have implemented a recursive feature elimination with cross-validation using the support vector machine (SVM) approach for refined feature selection. Building on this, we developed six machine learning models, including logistic regression, k-Nearest Neighbors (k-NN), Naive Bayes, Random Forest, Gradient Boosting, and Multilayer Perceptron Neural Network, to evaluate their performance. Findings: The Gradient Boosting Classifier excelled, achieving a median recall of 92.17% and outstanding metrics such as area under the receiver operating characteristics curve (AUC) with a median of 68%, alongside median accuracy and precision scores of 76%. Through our machine learning analysis, we identified 31 genes significantly associated with diabetes traits, highlighting their potential as biomarkers and targets for diabetes management strategies. Conclusion: Particularly noteworthy were the Gradient Boosting Classifier and Multilayer Perceptron Neural Network, which demonstrated potential in diabetes outcome prediction. We recommend future investigations to incorporate larger cohorts and a wider array of predictive variables to enhance the models' predictive capabilities.

Keywords: diabetes, machine learning, prediction, biomarkers

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Authors: Abdelaziz Nasr

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This work conducted numerical simulations to examine the impact of the static electric field on a falling-film evaporation system. A constant electric field can alter the dynamics of a liquid film by modifying the heat and mass transfer properties of the system. The geometry problem consists of two parallel plates in a vertical channel, with the left plate experiencing a constant heat flux and the liquid flowing downward over it, while the right plate remains dry and maintains a constant temperature. The gaseous component consists of dry air and water vapor, whilst the liquid component comprises a thin coating of water. The results suggest that the electric field's impact on heat and mass transport, as well as the evaporation of the liquid sheet, is minimal. Experimental evidence demonstrates that the electric field exerts a minor influence on heat, mass transport, and liquid film evaporation at elevated electric field intensities.

Keywords: electric field, evaporation, liquid film, heat and mass transfer

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Authors: Apolinar Picado, Ronald Solís, Rafael Gamero

Abstract:

The thin-layer drying characteristics of instant coffee solution were investigated in a laboratory tunnel dryer. Drying experiments were carried out at three temperatures (80, 100 and 120 °C) and an air velocity of 1.2 m/s. Drying experimental data obtained are fitted to six (6) thin-layer drying models using the non-linear least squares regression analysis. The acceptability of the thin-layer drying model has been based on a value of the correlation coefficient that should be close to one, and low values for root mean square error (RMSE) and chi-square (x²). According to this evaluation, the most suitable model for describing drying process of thin-layer instant coffee solution is the Page model. Further, the effective moisture diffusivity and the activation energy were computed employing the drying experimental data. The effective moisture diffusivity values varied from 1.6133 × 10⁻⁹ to 1.6224 × 10⁻⁹ m²/s over the temperature range studied and the activation energy was estimated to be 162.62 J/mol.

Keywords: activation energy, diffusivity, instant coffee, thin-layer models

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Authors: Lucie Novakova, Petr Homola, Vaclav Kafka

Abstract:

Asymmetric incremental sheet forming (AISF) could significantly reduce costs incurred by the fabrication of complex industrial components with a minimal environmental impact. The AISF experiments were carried out on commercially pure titanium (Ti-Gr2), Timetal (15-3-3-3) alloy, and Ti-6Al-4V (Ti-Gr5) alloy. A special testing geometry was used to characterize the titanium alloys properties from the point of view of the forming zone and titanium structure effect. The structure and properties of the materials were assessed by means of metallographic analyses and microhardness measurements.The highest differences in the parameters assessed as a function of the sampling zone were observed in the case of alpha-phase Ti-Gr2at the expense of the most substantial sheet thinning occurrence. A springback causes a smaller stored deformation in Timetal (β alloy) resulting in less pronounced microstructure refinement and microhardness increase. Ti-6Al-4V alloy exhibited early failure due to its poor formability at ambient temperature.

Keywords: incremental forming, metallography, hardness, titanium alloys

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Authors: L. Foudia, K. Haddadi, M. Reffas

Abstract:

First principles study of structural, elastic, electronic and optical properties of the monoclinic perovskite type ScRhO₃ has been reported using the pseudo-potential plane wave method within the local density approximation. The calculated lattice parameters, including the lattice constants and angle β are in excellent agreement with the available experimental data, which proving the reliability of the chosen theoretical approach. Pressure dependence up to 20 GPa of the single crystal and polycrystalline elastic constants has been investigated in details using the strain-stress approach. The mechanical stability, ductility, average elastic wave velocity, Debye temperature and elastic anisotropy were also assessed. Electronic band structure and density of states (DOS) demonstrated its semiconducting nature showing a direct band gap of 1.38 eV. Furthermore, several optical properties, such as absorption coefficient, reflectivity, refractive index, dielectric function, optical conductivity and electron energy loss function have been calculated for radiation up to 40 eV.

Keywords: ab-initio, perovskite, DFT, band gap.

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Authors: Siddhant Sethi, Yasuharu Takashima, Shigetaka Nakamura, Kenzo Fujimoto

Abstract:

Site-directed mutagenesis is a renowned technique to introduce specific mutations in the genome. To achieve site-directed mutagenesis, many chemical and enzymatic approaches have been reported in the past like disulphite induced genome editing, CRISPR-Cas9, TALEN etc. The chemical methods are invasive whereas the enzymatic approaches are time-consuming and expensive. Most of these techniques are unusable in the cellular application due to their toxicity and other limitations. Photo-chemical cytosine deamination, introduced in 2010, is one of the major technique for enzyme-free single-point mutation of cytosine to uracil in DNA and RNA, wherein, 3-cyanovinylcarbazole nucleoside (CNVK) containing oligodeoxyribonucleotide (ODN) having CNVK at -1 position to that of target cytosine is reversibly crosslinked to target DNA strand using 366 nm and then incubated at 90ºC to accommodate deamination. This technique is superior to enzymatic methods of site-directed mutagenesis but has a disadvantage that it requires the use of high temperature for the deamination step which restricts its applicability in the in vivo applications. This study has been focused on improving the technique by reducing the temperature required for deamination. Firstly, the photo-cross-linker, CNVK has been modified by replacing cyano group attached to vinyl group with methyl ester (OMeVK), amide (NH2VK), and carboxylic acid (OHVK) to observe the acceleration in the deamination of target cytosine cross-linked to vinylcarbazole derivative. Among the derivatives, OHVK has shown 2 times acceleration in deamination reaction as compared to CNVK, while the other two derivatives have shown deceleration towards deamination reaction. The trend of rate of deamination reaction follows the same order as that of hydrophilicity of the vinylcarbazole derivatives. OHVK being most hydrophilic has shown highest acceleration while OMeVK is least hydrophilic has proven to be least active for deamination. Secondly, in the related study, the counter-base of the target cytosine, guanine has been replaced by inosine, 2-aminopurine, nebularine, and 5-nitroindole having distinct hydrogen bonding patterns with target cytosine. Among the ODNs with these counter bases, ODN with inosine has shown 12 fold acceleration towards deamination of cytosine cross-linked to CNVK at physiological conditions as compared to guanosine. Whereas, when 2-aminopurine, nebularine, and 5-nitroindole were used, no deamination reaction took place. It can be concluded that inosine has potential to be used as the counter base of target cytosine for the CNVK mediated photo-cross-linking induced deamination of cytosine. The increase in rate of deamination reaction has been attributed to pattern and number of hydrogen bonding between the cytosine and counter base. One of the important factor is presence of hydrogen bond between exo-cyclic amino group of cytosine and the counter base. These results will be useful for development of more efficient technique for site-directed mutagenesis for C → U transformations in the DNA/RNA which might be used in the living system for treatment of various genetic disorders and genome engineering for making designer and non-native proteins.

Keywords: C to U transformation, DNA editing, genome engineering, ultra-fast photo-cross-linking

Procedia PDF Downloads 240