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Showing records 3934 to 3958 of 43292. [First] Page: 1 155 156 157 158 159 160 161 162 163 Last
Analysis of the Influence of Micro-Pore Structure on Oil Occurrence Using Nano-CT Scanning and Nuclear Magnetic Resonance Technology: An Example from Chang 8 Tight Sandstone Reservoir, Jiyuan, Ordos Basin
Xinglei Song, Hui Gao, Congjun Feng, Ping Yi, Chen Wang, Teng Li.
April 28, 2023 (v1)
Subject: Materials
Keywords: dynamic occurrence, nano CT scanning, nuclear magnetic resonance, pore size, tight oil, tight sandstone.
The micro-pore structure of a tight sandstone reservoir remarkably impacts the occurrence characteristics of the tight oil. The micro-pore structure of the Jiyuan Chang 8 tight sandstone reservoir in the Ordos Basin was examined in this research using a core physical property test, an environmental scanning electron microscope, thin section identification, and high-pressure mercury intrusion. Using nano-CT scanning and nuclear magnetic resonance technologies, representative core samples were chosen for studies evaluating the tight oil occurrence statically and dynamically. The micro-pore structure effect of a tight sandstone reservoir on the occurrence of tight oil was investigated, and the occurrence of tight oil in the reservoir forming process was discussed. It was significant to the study of tight oil in the reservoir forming process in Ordos Basin. Findings indicated that the Chang 8 reservoir in Jiyuan, Ordos Basin has poor physical properties and exhibits a high degree of hetero... [more]
Fixed Bed Batch Slow Pyrolysis Process for Polystyrene Waste Recycling
Galo Albor, Amin Mirkouei, Armando G. McDonald, Ethan Struhs, Farid Sotoudehnia.
April 28, 2023 (v1)
Keywords: plastic waste, polystyrene, pyrolysis oil, slow pyrolysis, thermochemical conversion.
This study evaluates the potential of recycling polystyrene (PS) plastic wastes via a fixed bed (batch) slow pyrolysis reactor. The novelty lies in examining the reactor design, conversion parameters, and reaction kinetics to improve the process yield, activation energy, and chemical composition. PS samples were pyrolyzed at 475−575 °C for 30 min under 10−15 psi. Process yield and product attributes were evaluated using different methods to understand PS thermal degradation characteristics better. The results show that PS decomposition started within 2 min from all temperatures, and the total decomposition point of 97% at 475 °C at approximately 5 min. Additionally, analytical results indicate that the average necessary activation energy is 191 kJ/mol. Pyrolysis oil from PS was characterized by gas chromatography−mass spectrometry. The results show that styrene was produced 57−60% from all leading oil compounds (i.e., 2,4-diphenyl-1-butene, 2,4,6-triphenyl-1-hexene, and toluene), and 4... [more]
Reactor Temperature Control Based on Improved Fractional Order Self-Anti-Disturbance
Xiaowei Tang, Bing Xu, Zichen Xu.
April 28, 2023 (v1)
Keywords: fractional order, reactor, self-disturbance control, temperature control.
In the chemical industry, a reactor is an absolutely necessary container. The fact that its dynamic qualities are nonlinear and unknown, however, is what causes the temperature to deviate from the value that was specified. As a result, the typical PID control cannot fulfill the prerequisites of the production process. A new nonlinear function is presented to replace the function that was previously used, and a temperature controller that is based on better fractional order active disturbance rejection is devised. On the basis of a new fractional order temperature detector (FOTD), a new fractional order equilibrium state observer (FOESO), and nonlinear function, an improved fractional order active disturbance rejection controller has been developed. A model of the reactor was created, and the dynamic properties of temperature control were investigated. By simulation and experimentation, it was demonstrated that the strategy has a number of benefits and is effective. In this approach, th... [more]
Thermal-Mechanical Analysis of a Metro Station’s Concrete Structure
Zongyuan Ma, Wei Li, Zhaoyu Li, Xuefei Ruan, Kai Jiao.
April 28, 2023 (v1)
Subject: Materials
Keywords: concrete structure of a metro station, cracking prediction, temperature stress, thermal-mechanical analysis.
The problem of temperature variation in mass concrete construction is a crucial problem in civil engineering. The problems of the temperature field, damaged areas, and the cracking of the structure during the construction process of concrete pouring are analyzed in this paper. An elastic and damaged constitutive model for concrete and a fully coupled analysis method for analyzing the temperature-stress field was proposed to simulate and predict the construction process of a concrete structure in a metro station. The influence of different concrete compositions and material properties was not taken into account in this study. The results show that the temperature-stress complete coupling analysis method can be applied to the calculation and analysis of cracking in a concrete structure that is caused by internal temperature variations during the pouring process of complex concrete structures. An efficient method and research approach is proposed by this study to analyze the damage and cr... [more]
Comparison Study on the Water-to-Biomass Ratio in Hydrothermal Carbonization of Fresh Seaweed
Sepideh Soroush, Frederik Ronsse, Jihae Park, Philippe M. Heynderickx.
April 28, 2023 (v1)
Subject: Materials
Keywords: Biomass, hydrochar, moisture content, waste seaweed, water to biomass ratio.
Upgrading wet biomass to char via hydrothermal carbonization is a promising method to produce valuable resources for adsorption of organic impurities. In this work, a fresh green seaweed, Ulva pertusa, was investigated to demonstrate the effects of pre-drying and pre-washing on the process and the hydrochar production. Surface moisture and bound moisture were found to affect this process. Hydrochar produced from fresh seaweed with additional water showed similar adsorption capacity to fresh seaweed without additional water and 38% higher than hydrochar from soaked dry seaweed. This was supported by FTIR spectra analysis, which showed that these hydrochars produced from fresh seaweed without additional water have the highest proportion of carboxyl functional groups.
Textural, Rheological, and Sensory Modifications in Oaxaca Cheese Made with Ultrasonicated Raw Milk
Luis M. Carrillo-López, Mariana Huerta-Jiménez, Simón Morales-Rodríguez, Jesús R. Gámez-Piñón, Diego E. Carballo-Carballo, Néstor Gutiérrez-Méndez, Alma D. Alarcón-Rojo.
April 28, 2023 (v1)
Subject: Materials
Keywords: high-intensity ultrasound, microstructure, Oaxaca cheese, sensory acceptability, textural properties.
In this research, we evaluated the effects of different frequencies (25 and 45 kHz) and times (15 and 30 min) of high-intensity ultrasound (HIU) applied to fresh raw milk on the textural properties of Oaxaca cheese. When HIU was applied for 15 min, the cheese melting time was reduced by up to 23.4 s compared to the control. The cheeses produced with ultrasonicated milk at 45 kHz presented larger melting and exudate areas. They were softer, but consumer acceptability was lower. Frequencies of 25 and 45 kHz (15 or 30 min) reduced the temperature of the solid−liquid transition by 1.9−3.6 °C and 0.6−1.8 °C, respectively, compared to controls. Consequently, the melting time in ultrasonicated cheese was significantly reduced. The strands were perfectly aligned and well organized in the direction of stretching with 25 kHz ultrasonication. In addition, these cheeses were more consistent, chewy, and rubbery. Consequently, they were preferred and more accepted in flavor, aroma, and texture, with... [more]
Thermal Stability, Kinetic Analysis, and Safe Temperature Assessment of Ionic Liquids 1-Benzyl-3-Methylimidazolium Bis (Trifluoromethylsulfonyl) Imide for Emerging Building and Energy Related Field
Li-Chi Hung, Nai-Hsin Pan.
April 28, 2023 (v1)
Subject: Materials
Keywords: building polymer, green solvents, thermal hazard, thermochemical reactivity, thermogravimetric analysis.
Ionic liquids are molten salts that possess excellent chemical and thermal stability. Due to their inherent qualities in green chemistry, ionic liquids have been identified as potential substitutes for traditional organic solvents. These useful physical and chemical properties lead to some promising applications in fields such as building polymer engineering alternative materials and renewable energy technologies. Although they are classified as green solvents, these new solvents exist in a high-temperature environment, which is related to thermochemical reactivity and safety; there are few related studies. To analyze the possible high-temperature application environment of ionic liquids in the future, we analyzed the new ionic liquid 1-Benzyl-3-methylimidILlium bis (trifluoromethylsulfonyl) imide ([BZMIM][TF2N]), which lacks thermal analysis basis. This study used thermogravimetric analysis as the basis of the reaction model. We calculated the thermal hazard, kinetics, and parameter a... [more]
Pore Distribution Characteristics of Different Lithofacies Shales: Evidence from Scanning Electron Microscopy
Junjie Wang, Shuangfang Lu, Pengfei Zhang, Qi Zhi, Hongsheng Huang.
April 28, 2023 (v1)
Subject: Materials
Keywords: Dongying Sag, lacustrine shale, pore morphology, pore size, scanning electron microscopy.
To disclose the pore distribution characteristics of different lithofacies lacustrine shales, ten samples collected from the Shahejie Formation, Dongying Sag, Bohai Bay Basin, China, were examined using argon ion beam milling−scanning electron microscopy (SEM). A quantitative method was adopted to characterize shale pore distributions based on the SEM images. Mercury intrusion capillary pressure was employed to determine the pore throat size distributions of the shales. The SEM images indicated that in shale reservoirs, interparticle pores at the edges of brittle particles and intraparticle pores in clay mineral aggregates primarily contribute to the reservoir spaces and that in calcite-rich shales, dissolution pores provide secondary reservoir space. Among the morphologies of dissolution, intraparticle, and interparticle pores, the morphology of the dissolution pores is the simplest, followed by those of intraparticle and interparticle pores in that order. Clay and felsic minerals pri... [more]
Microstructure, Wear Resistance and Corrosion Performance of Inconel 625 Layer Fabricated by Laser/Ultra-High Frequency (UHF) Induction Hybrid Deposition
Rui Sun, Yuhang Qiao, Xinhong Li, Yongjun Shi, Xiaogang Wang.
April 28, 2023 (v1)
Subject: Materials
Keywords: corrosion resistance, laser deposition, microstructure, ultra-high frequency (UHF) induction heat, wear resistance.
In order to avoid microstructure degradation caused by low frequency induction heat in laser-induction hybrid deposition, this paper proposes a laser/ultra-high frequency (UHF) induction hybrid deposition method. Microstructure observation is carried out to reveal the effect of UHF induction heat on the microstructure of the deposited layer. Results indicate that the laser-UHF induction hybrid deposited layer, under a current density of 1.14 × 108 A/m2, exhibits a finer microstructure and fewer Laves phases than that of the laser deposited layer. As the current density increases from 1.01 × 108 A/m2 to 1.14 × 108 A/m2, the microstructure of the laser-UHF induction hybrid deposited layer is significantly refined; however, as the current density further increases, the microstructure is only slightly further refined, since the enhanced thermal effect, along with the increasing current density, may help grain growth. Wear test demonstrates that the laser-UHF induction hybrid deposited laye... [more]
Techniques Used for Bond Strengthening of Sub-Standard Splices in Concrete: A Review Study
Sabry Fayed, Walid Mansour, Taher A. Tawfik, Peter Sabol, Dušan Katunský.
April 28, 2023 (v1)
Keywords: bond failure, bond strength, bonded length, CFRP, confinement, insufficient lap splice length, jacketing, RC members, review, strengthening methods, UHPC.
Bar splicing is considered an essential part of the construction process of reinforced concrete (RC) due to the ease of installation in construction, transportation constraints, and restricted length of reinforcing bars. Splices serve the primary role of joining reinforcement bars in standard RC elements such as columns, walls, beams, slabs, and joints. Bond behavior between the bars and the concrete is one of the fundamental qualities required for appropriate RC structure design and analysis, as it affects serviceability and ultimate limit states. The most common failure found in lap splice locations is debonding, which occurs at the splice region and insufficient lapped length is considered as the primary cause because of design or construction mistakes, design by outmoded code, and natural catastrophes. As a result, strengthening existing substandard splices in RC structures is critical. The purpose of this research is to analyze and summarize experimental strengthening solutions fo... [more]
Hydroxypropyl-β-Cyclodextrin-Glycerol-Assisted Extraction of Phenolics from Satureja montana L.: Optimization, Anti-Elastase and Anti-Hyaluronidase Properties of the Extracts
Marijan Marijan, Lejsa Jakupović, Marijana Zovko Končić.
April 28, 2023 (v1)
Subject: Biosystems
Keywords: cosmeceutical extracts, cyclodextrin-glycerol-assisted extraction, luteolin-7-O-glucoside, rosmarinic acid, Satureja montana, ultrasound-assisted extraction.
A green method for hydroxypropyl-β-cyclodextrin-glycerol-assisted extraction (HCGAE) of bioactive phenolics from S. montana, Lamiaceae was optimized using Box-Behnken design and response surface methodology and compared conventional water/ethanol-based extraction. The procedure was aimed at obtaining extracts with the maximum content of total phenols (TP), flavonoids (TF), dihydroxycinnamic acids (TDCA), rosmarinic acid (RA), and luteolin 7-O-glucoside (LG). The impact of glycerol content (0−70%), 2-hydroxypropyl-β-cyclodextrin content (0−0.4 mmol), temperature (20−70 °C), herbal material weight (0.3−0.8 g), extraction duration (5−25 min), and ultrasound power (144−720 W) on the extraction efficiency was analyzed. Four extracts with maximum amounts of target phenols, OPT-TP (5.93 mg/mL), OPT-TDCA-RA (4.17 mg/mL and 1.16 mg/mL, respectively), OPT-TF (0.99 mg/mL), and OPT-LG (0.28 mg/mL) were prepared. Comparison of the content of TDCA, TF, RA, and LG with those obtained in water/ethanol... [more]
Benefits and Limitations of Artificial Neural Networks in Process Chromatography Design and Operation
Mourad Mouellef, Florian Lukas Vetter, Jochen Strube.
April 28, 2023 (v1)
Subject: Materials
Keywords: artificial neural networks, chromatography modeling, hybrid models, Machine Learning, mixed-mode chromatography, parameter estimation.
Due to the progressive digitalization of the industry, more and more data is available not only as digitally stored data but also as online data via standardized interfaces. This not only leads to further improvements in process modeling through more data but also opens up the possibility of linking process models with online data of the process plants. As a result, digital representations of the processes emerge, which are called Digital Twins. To further improve these Digital Twins, process models in general, and the challenging process design and development task itself, the new data availability is paired with recent advancements in the field of machine learning. This paper presents a case study of an ANN for the parameter estimation of a Steric Mass Action (SMA)-based mixed-mode chromatography model. The results are used to exemplify, discuss, and point out the effort/benefit balance of ANN. To set the results in a wider context, the results and use cases of other working groups a... [more]
On the Energy Performance and Energy Saving Potential of the Pharmaceutical Industry: A Study Based on the Italian Energy Audits
Giacomo Bruni, Chiara Martini, Fabrizio Martini, Marcello Salvio.
April 28, 2023 (v1)
Subject: Energy Policy
Keywords: energy audits (EAs), Energy Efficiency, energy management, energy performance improvement actions (EPIA), energy performance indicators (EnPI), energy transition, pharmaceutical industry, specific energy consumption (SEC).
The growing attention towards environmental sustainability in the pharmaceutical industry and increased awareness of the potential for improving energy performance are justified by the fact that the sector is energy intensive. However, the variety of the processes and the lack of data about production and energy consumption make it difficult to calculate Energy Performance Indicators (EnPIs) as much as to list Energy Performance Improvements Actions (EPIAs). This work elaborates data, such as final energy consumption and site characteristics, from 84 mandatory Italian Energy Audits (EAs) to calculate the mean and standard deviation of site-level EnPIs. Additionally, the suggested and implemented EPIAs are analyzed to describe achieved and potential savings. The results show what follows. In the typical pharmaceutical plant, around 70% of energy is used in auxiliary services, and its use is not related to production. For this reason, EnPIs calculated both with respect to mass production... [more]
Combustion Chamber Optimization for Dual-Fuel Biogas−Diesel Co-Combustion in Compression Ignition Engines
Stefano Caprioli, Antonello Volza, Francesco Scrignoli, Tommaso Savioli, Enrico Mattarelli, Carlo Alberto Rinaldini.
April 28, 2023 (v1)
Keywords: 3D-CFD analysis, biogas, bowl optimization, dual fuel, injection, micro-cogeneration.
Micro-cogeneration with locally produced biogas from waste is a proven technique for supporting the decarbonization process. However, the strongly variable composition of biogas can make its use in internal combustion engines quite challenging. Dual-fuel engines offer advantages over conventional SI and diesel engines, but there are still issues to be addressed, such as the low-load thermodynamic efficiency and nitrogen oxide emissions. In particular, it is highly desirable to reduce NOx directly in the combustion chamber in order to avoid expensive after-treatment systems. This study analyzed the influence of the combustion system, especially the piston bowl geometry and the injector nozzle, on the performance and emissions of a dual-fuel diesel−biogas engine designed for micro-cogeneration (maximum electric power: 50 kW). In detail, four different cylindrical piston bowls characterized by radii of 23, 28, 33 and 38 mm were compared with a conventional omega-shaped diesel bowl. Moreov... [more]
Evaluation of Crude Oil Wax Dissolution Using a Hydrocarbon-Based Solvent in the Presence of Ionic Liquid
Muhammad Rahmat Syafiq Zainal Abidin, Mohd Hilmi Noh, Muhammad Moniruzzaman, Masahiro Goto.
April 28, 2023 (v1)
Keywords: crude oil wax, gas condensate, hydrocarbon solvent, ionic liquid.
The current alternative of using aromatic-based wax soak solvents has been found to be hazardous and imposes a high cost on field expenditures. These solvents are widely used in the oil and gas industry to soften up wax before the pigging process. However, their impacts on the environment are quite concerning. Plus, they also impose hazardous exposure and are found to be damaging to both plastic and rubber hoses. To replace the current alternative with other hydrocarbon-based wax soak solvents, ionic liquids were found to have the capability to increase the solvent power capabilities and the efficiency of wax soak solvent in dissolving heavy crude oil. To optimise the application of hydrocarbon solvents and ionic liquid in wax dissolution, the affinity of ionic liquids in three solvents was studied. The solvents were condensate, ethyl acetate, and xylene. It was found that from four types of ionic liquids tested, only BMIMCL and HMIMBr were miscible in all three of the solvents used. D... [more]
Determination of the Antioxidant and Antiproliferative Properties of Pomegranate Peel Extract Obtained by Ultrasound on HCT-116 Colorectal Cancer Cell Line
Christie Habchi, Adnan Badran, Mortada Srour, Anis Daou, Elias Baydoun, Kamar Hamade, Akram Hijazi.
April 28, 2023 (v1)
Subject: Biosystems
Keywords: antioxidant, antiproliferative, colorectal cancer, maceration, pomegranate, ultrasound assisted extraction.
Colorectal cancer (CRC) is one of the most common cancers in the world. When treating patients, therapeutic agents have side effects; hence, the use of natural compounds found in medicinal plants including pomegranate. Ultrasound assisted extraction (UAE) is a new technique evolving to the detriment of traditional methods such as maceration. In this study, we investigated the antioxidant and anticancer effect of pomegranate peel extracts obtained by maceration and UAE at three different ultrasonic power levels (P1 = 10 W; P2 = 50 W; P3 = 100 W) on HCT-116 colorectal cancer cells. Phytochemical screening highlighted the presence of primary and secondary metabolites in pomegranate peels. In addition, the ethanolic extract obtained by UAE at 50 W was shown to be the most concentrated in phenolic and flavonoid compounds and have the most powerful antioxidant activity, which reached a maximum activity of 92% as determined by DPPH test. Similarly, the MTT cell viability test showed that the... [more]
Complicated Time-Constrained Project Scheduling Problems in Water Conservancy Construction
Song Zhang, Xiaokang Song, Liang Shen, Lichun Xu.
April 28, 2023 (v1)
Keywords: Genetic Algorithm, project scheduling, resource-constrained, water conservancy.
Water conservancy project scheduling is an extension to the classic resource-constrained project scheduling problem (RCPSP). It is limited by special time constraints called “forbidden time windows” during which certain activities cannot be executed. To address this issue, a specific RCPSP model is proposed, and an approach is designated for it which incorporates both a priority rule-based heuristic algorithm to obtain an acceptable solution, and a hybrid genetic algorithm to further improve the quality of the solution. In the genetic algorithm, we introduce a new crossover operator for the forbidden time window and adopt double justification and elitism strategies. Finally, we conduct simulated experiments on a project scheduling problem library to compare the proposed algorithm with other priority-rule based heuristics, and the results demonstrate the superiority of our algorithm.
Single-Cell Techniques in Environmental Microbiology
Yongping Shan, Yuting Guo, Wentao Jiao, Ping Zeng.
April 28, 2023 (v1)
Keywords: flow cytometry, identification, isolation, observation, single-cell techniques.
Environmental microbiology has been an essential part of environmental research because it provides effective solutions to most pollutants. Hence, there is an interest in investigating microorganism behavior, such as observation, identification, isolation of pollutant degraders, and interactions between microbial species. To comprehensively understand cell heterogeneity, diverse approaches at the single-cell level are demanded. Thus far, the traditional bulk biological tools such as petri dishes are technically challenging for single cells, which could mask the heterogeneity. Single-cell technologies can reveal complex and rare cell populations by detecting heterogeneity among individual cells, which offers advantages of higher resolution, higher throughput, more accurate analysis, etc. Here, we overviewed several single-cell techniques on observation, isolation, and identification from aspects of methods and applications. Microscopic observation, sequencing identification, flow cytome... [more]
Corn Extrudates Enriched with Health-Promoting Ingredients: Physicochemical, Nutritional, and Functional Characteristics
Alina Culețu, Iulia Elena Susman, Mihaela Mulțescu, Șerban Eugen Cucu, Nastasia Belc.
April 28, 2023 (v1)
Subject: Biosystems
Keywords: antioxidant capacity, condiments, corn, extrudates, glycemic index, phenolic compounds, plants, protein sources.
The objective of this study was to evaluate the effects of different types of powder additions on the properties of corn extrudates. The following ingredients, which are good sources of bioactive compounds, were used to substitute corn flour: legume protein sources (2% pea, 5% broccoli, and 5% lucerne), plants (15% beetroot and 15% rosehip), and condiments (2% chili, 2% turmeric, 2% paprika, and 2% basil). The total polyphenolic content (TPC) and antioxidant activity (AA) increased when the corn flour was replaced with the different types of ingredients. The highest TPC was found for rosehip followed by the beet, basil, and broccoli additions. Compared to the raw formulations, all the extrudates, except the rosehip extrudate, showed a decrease in the TPC ranging from 11 to 41%, with the smallest loss (11%) occurring for basil and the highest loss (41%) occurring for the control extrudate, respectively. The same observation was recorded for the AA. For the extrudate enriched with rosehi... [more]
Antimicrobial and Photocatalytic Activities of Selenium Nanoparticles Synthesized from Elaeagnus indica Leaf Extract
Dhatchanamoorthi Indhira, Arumugam Aruna, Krishnamoorthy Manikandan, Mohammed F. Albeshr, Abdulwahed Fahad Alrefaei, Ramachandran Vinayagam, Arumugam Kathirvel, Selvaraj Ranjith Priyan, Govindan Suresh Kumar, Ramalingam Srinivasan.
April 28, 2023 (v1)
Subject: Materials
Keywords: antimicrobials, Elaeagnus indica, green synthesis, photocatalytic activity, Se NPs.
Selenium nanoparticles (Se NPs) have recently received much interest due to their low toxicity, high bioavailability, and wide applications. This study synthesized Se NPs using selenious acid as a starting material and leaf extract from Elaeagnus indica as a reducing agent. Spectroscopic and electron microscopy investigations have demonstrated the production of aggregated amorphous Se NPs with phytochemicals. Furthermore, the reduction of selenious acid into Se NPs by phytochemicals present in the leaf extract of E. indica was confirmed in a prominent band at 269 nm in the UV-visible spectrum. The biosynthesized selenium nanoparticles have a 10−15 nm particle size distribution. The agar well diffusion assay exhibited remarkable dose-dependent, wide-spectrum antimicrobial efficacy of the Se NPs against all the tested microorganisms. Moreover, the lowest minimum inhibitory concentration (10 µg/mL) was noted against Salmonella Typhimurium and Fusarium oxysporum. The prepared Se NPs degrad... [more]
Establishment of a Research Focus on Resilient Sustainable Climate Neutral Agricultural Production—Resilient Farming Initiative
Alexander Uhl, Axel Schmidt, Martin Tegtmeier, Andreas Wenzel, Frank Beneke, Jochen Strube.
April 28, 2023 (v1)
Keywords: agri-photovoltaics, cascade utilization, circular economy, climate neutrality, cultivation and harvesting technology, digitalization, energy and resource efficiency, resilience, robotics, waste valorization.
Efficient and sustainable agricultural production is a pivotal factor in meeting the nutritional needs of an expanding global population. However, it is imperative to optimize national, regional and local effectiveness to support government initiatives towards climate neutrality and resilience, while simultaneously ensuring economic viability for farmers. A significant reduction in the cost of goods must be accompanied by a decrease in their global warming potential contribution to maintain competitiveness in the world market. As such, it is necessary to adopt practices that enhance productivity while minimizing environmental impacts. This paper discusses potential solutions for the sustainable enlargement of botanical product portfolios towards essential oil products and natural extracts for value-added products, such as natural pharmaceuticals, cosmetics, agrochemicals and materials by direct waste valorization. Contributions from the fields of automation and digitalization provide t... [more]
Design and Modelling of Heat-Coupled Storage System with High- and Low-Pressure Bypass: Electrothermal Characteristics and Peak Regulating Performance
Han Yang, Sun Tao, Ma Honghe.
April 28, 2023 (v1)
Keywords: Aspen Plus, heat-coupled storage system, high- and low-pressure bypass, peak regulation.
To achieve a balance between supply and demand during cogeneration system operation, it is necessary to improve the peak regulation capacity and regulatory flexibility of the unit. Considering the excellent performance of energy storage systems, a heat-coupled storage system with high- and low-pressure bypass is proposed to increase peak regulation capacity. Employing a 300 MW heating unit as the research object, thermal system models of a traditional-pumping steam-heating system, a high- and low-pressure bypass heating system, and a coupled system were built using Aspen Plus software. The electric heating characteristics of the three systems, as well as the peak regulation capacity and peak regulation depth of the coupled system, were analysed under different storage and heat release loads. Results indicate that the high- and low-voltage bypass system and the coupled system both improve the peak capacity and control flexibility of the unit. Moreover, the coupled system has a greater i... [more]
Influence of Estimators and Numerical Approaches on the Implementation of NMPCs
Fernando Arrais Romero Dias Lima, Ruan de Rezende Faria, Rodrigo Curvelo, Matheus Calheiros Fernandes Cadorini, César Augusto García Echeverry, Maurício Bezerra de Souza Jr, Argimiro Resende Secchi.
April 28, 2023 (v1)
Keywords: CEKF, estimators, Nonlinear Model Predictive Control, Numerical Methods, orthogonal collocation.
Advanced control strategies, together with state-estimation methods, are frequently applied to nonlinear and complex systems. It is crucial to understand which of these are the most efficient methods for the best use of these approaches in a chemical process. In the current work, nonlinear model predictive control (NMPC) approaches were developed that considered three numerical methods: single shooting (SS), multiple shooting (MS), and orthogonal collocation (OC). Their performance was compared against the Van de Vusse reactor benchmark while considering set-point changes, unreachable set-point, disturbances, and mismatches. The results showed that the NMPC based on OC presented less computational cost than the other approaches. The extended Kalman filter (EKF), constrained extended Kalman filter (CEKF), and the moving horizon estimator (MHE) were also developed. The estimators’ performance was compared for the same benchmark by considering the computational cost and the mean squared e... [more]
Design and Optimization of the Training Device for the Employment of Hydraulic Rescue Tools in Traffic Accidents
Michal Ballay, Bohuš Leitner, Lenka Jakubovičová.
April 28, 2023 (v1)
Subject: Optimization
Keywords: beam element, design, experiment, FEM analysis, firefighters’ units, hydraulic rescue tools, Optimization, training device prototype.
This paper is concerned with the design and structural optimization of a training device for operators of a hydraulic rescue tool employed during traffic accidents, in conjunction with the improvement of the technical procedures used in such situations. Changes in the design process and subsequent production in the motor industry frequently result in an increased impact resistance of the used structural components. This applies, also, to extrication works and frequently used technical equipment. This paper presents its findings on the design process for the prototype of a training device designed for the extrication cutting drill with the assistance of a hydraulic rescue tool. The primary part of the research was dedicated to structural optimization; therefore, parameter dimensioning of the training device’s prototype was implemented. The device’s mechanical resistance, sturdiness, and stability during the implementation of hydraulic tools were also taken into account. A secondary part... [more]
Particle Deposition Pattern on an Automotive Diesel Filter Using an Eulerian Probability Density Function Method
Luis Valiño, Radu Mustata, Juan Hierro, Juan Luis Hernández, María José García, Carlos Blasco, Yi-Tung Chen, Lung-Wen Chen, Prosun Roy.
April 28, 2023 (v1)
Keywords: Eulerian probability density function, filter, particle size distribution, two-phase flows.
A full 3D numerical simulation of the two-phase flow made up of (bio)diesel and particles, has been carried out to reproduce the deposition pattern of particles in a BOSCH automotive filter. From a probability density function (PDF), a simple Eulerian-Eulerian two-phase model is proposed for diesel and particles. The proposed formulation allows for a detailed description of the relationship between the velocity and size of the particles. A Brinkman-Darcy approximation has been considered for the flow through the filtering paper and is proved to be sufficient for the typical filter working conditions. The new tool is able to reproduce the deposition pattern shown by the used filters.
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