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Showing records 36287 to 36311 of 36336. [First] Page: 1 1449 1450 1451 1452 1453 1454 Last
Development of a SPE-HPLC-PDA Method for the Quantification of Phthalates in Bottled Water and Their Gene Expression Modulation in a Human Intestinal Cell Model
Vincenzo Ferrone, Pantaleone Bruni, Teresa Catalano, Federico Selvaggi, Roberto Cotellese, Giuseppe Carlucci, Gitana Maria Aceto
February 17, 2023 (v1)
Keywords: Caco-2 cell line, colon disease, gene expression, HPLC, phthalates, pollutions, qRT-PCR
Phthalates are ubiquitous pollutants that are currently classified as endocrine disruptor chemicals causing serious health problems. As contaminants of food and beverages, they come into contact with the epithelium of the intestinal tract. In this work, a SPE-HPLC-PDA method for the determination of phthalates in water from plastic bottles was developed and validated according to the food and drug administration (FDA) guidelines. A chromatographic separation was achieved using a mobile phase consisting of ammonium acetate buffer 10 mM pH 5 (line A) and a mixture of methanol and iso-propanol (50:50 v/v, line B) using gradient elution. Several SPE cartridges and different pH values were investigated for this study, evaluating their performance as a function of recovery. Among these parameters, pH 5 combined with the SPE sep pack C18 cartridge showed the best performance. Finally, the proposed method was applied to the analysis of real samples, which confirmed the presence of phthalates.... [more]
The Spatial Effect and Threshold Characteristics of Green Technological Innovation on the Environmental Pollution of Thermal Power, etc., Air Pollution-Intensive Industrial Agglomeration in China
Jingkun Zhou, Yating Li, Juan Tian, Zhifei Ma
February 17, 2023 (v1)
Subject: Environment
Keywords: green technology innovation, industrial agglomeration, pollution-intensive industry, spatial Durbin model, threshold regression model
Serious air pollution has occurred in China since 2012. With the increasing investment in technological innovation in China, the role of green technological innovation in reducing air pollution has attracted more and more attention. By constructing the spatial Durbin model and threshold regression model and using the statistical data of China’s provinces, this study explores the spatial effects and threshold characteristics of China’s green technology innovation on the environmental pollution of China’s air pollution-intensive industrial agglomeration. The research objective is to find out the spatial effects and threshold characteristics of green technology innovation on the environmental pollution of China’s air pollution-intensive industrial agglomeration. The results show that thermal power, etc., air pollution-intensive industrial are important sources of sulfur dioxide emissions; however, their degree of concentration is gradually increasing, resulting in rising sulfur dioxide em... [more]
Gravitational Surface Vortex Formation and Suppression Control: A Review from Hydrodynamic Characteristics
Gaoan Zheng, Zeheng Gu, Weixin Xu, Bin Lu, Qihan Li, Yunfeng Tan, Chengyan Wang, Lin Li
February 17, 2023 (v1)
Keywords: gravitational surface vortex, hydrodynamic characteristics, hydropower energy conversion, hydropower station, vortex-induced vibration
The energy-conversion stability of hydropower is critical to satisfy the growing demand for electricity. In low-head hydropower plants, a gravitational surface vortex is easily generated, which causes irregular shock vibrations that damage turbine performance and input-flow stability. The gravitational surface vortex is a complex fluid dynamic problem with high nonlinear features. Here, we thoroughly investigate its essential hydrodynamic properties, such as Ekman layer transport, heat/mass transfer, pressure pulsation, and vortex-induced vibration, and we note some significant scientific issues as well as future research directions and opportunities. Our findings show that the turbulent Ekman layer analytical solution and vortex multi-scale modeling technology, the working condition of the vortex across the scale heat/mass transfer mechanism, the high-precision measurement technology for high-speed turbulent vortexes, and the gas−liquid−solid three-phase vortex dynamics model are the... [more]
Downtime Reduction with Fast Restart Function in a Beverage Production System
Chaiyan Jettanasen, Natthanon Phannil, Suntiti Yoomak, Surakit Thongsuk, Sulee Bunjongjit, Atthapol Ngaopitakkul
February 17, 2023 (v1)
Keywords: drinking water production system, fast restart function, ladder diagram, programmable logic controller (PLC), sensor system, Simatic Manager Step 7
Bottled-beverage production systems require considerable machinery and sophisticated control systems. A malfunction in the production system can result in machine stoppages, thereby decreasing productivity and resulting in the production output not meeting the required target. Therefore, the problem of frequent stoppages of the production system must be resolved. The ‘Fast Restart Function’ is a proposed feature that can help reduce machine downtime by decreasing the time required for the product to drain from the conveyor. In this study, using this strategy, the investigated manufacturing system’s efficiency increased from 86.81% to 90.29%, enabling an increase in the average production capacity by 27,187 bottles per day, i.e., a 3.48 percent increment of the daily capacity. When employed in inefficient production systems or systems facing frequent shutdowns, this system is of considerable value for mitigating production stoppages.
Numerical Simulation and Optimization of SCR-DeNOx Systems for Coal-Fired Power Plants Based on a CFD Method
Huifu Wang, Jian Sun, Yong Li, Zhen Cao
February 17, 2023 (v1)
Keywords: Computational Fluid Dynamics, concentration field, flow field, optimal design, SCR
In order to solve the problem of the uneven distribution of the flow and ammonia concentration field in the selective catalytic reduction (SCR) denitrification system of a 660 MW coal-fired power plant, a three-dimensional computational fluid dynamics (CFD) model was established at a scale of 1:1. The existing flow guide and ammonia fume mixing device were then calibrated and optimized. The relative standard deviation of the velocity field distribution upstream of the ammonia injection grid (AIG) was optimized from 15.4% to 9.9%, with a reasonable radius of the deflector at the inlet flue elbows, and the relative standard deviation of the velocity field distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 25.4% to 10.2% by adjusting the angle between the deflector and the wall plate of the inlet hood. Additionally, with the use of a double-layer spoiler ammonia fume mixing device, the relative standard deviation of the ammonia mass concentr... [more]
Using Particle Residence Time Distributions as an Experimental Approach for Evaluating the Performance of Different Designs for a Pilot-Scale Spray Dryer
Zelin Zhou, Timothy A. G. Langrish, Sining Cai
February 17, 2023 (v1)
Keywords: chamber design, particle residence time, spray drying, wall-deposit re-entrainment
The performances of four different designs for a pilot-scale spray dryer have been evaluated and compared based on experimentally measured particle residence time distributions (RTD), recovery rates and physical properties of spray-dried fresh skim milk. The RTDs have been measured using a dye pulse injection method, and the measurements have been fitted to models using continuous stirred-tank reactors in series (CSTR-TIS) for quantitative performance evaluation and comparison. Conical drying chambers and a box connection design have been used in the latest dryer design to reduce the amount of wall deposition and provide a smoother gas flow pattern. The particle-to-gas mean residence time ratio for the latest design is significantly closer to unity (1.6 s/s to 1.0 s/s) compared with earlier designs (2.6 s/s to 1.5 s/s). The latest design has a wider spread of RTD (n = 5−8) compared with earlier designs (n = 13−18), which may be linked to the recirculation zone in the box connection. Al... [more]
Density Functional Theory Study on the Adsorption of Fe(OH)2+ on Kaolinite Surface in Water Environment
Hongqiang Wu, Yuqi Miao, Yong Li, Huashan Yan, Jinbiao Tan, Sen Qiu, Hao Wu, Tingsheng Qiu
February 17, 2023 (v1)
Subject: Environment
Keywords: Adsorption, Fe, kaolinite, quantum chemistry
Fe impurity is abundant in rare earth leaching solutions. The optimal hydrate structure of Fe(OH)2+ was calculated based on the quantum chemical in the water environment to investigate the microscopic occurrence of Fe impurity on kaolinite surfaces. The adsorption structure and bonding mechanism (including outer and inner layer) of hydrate Fe(OH)2+ on the kaolinite (001) surface were investigated. According to the results, the stable hydrate form of Fe(OH)2+ is [Fe(OH)(H2O)5]2+. Hydrated Fe(OH)2+ has a tendency to adhere to the Si-O surface in the form of outer layer adsorption. Adsorbate tends to adsorb to the Ou (deprotonated upright hydroxyl) site, where it generates a monodentate adsorption compound, and to the Ol and Ou (deprotonated lying and upright hydroxyl) sites, where it generates a bidentate adsorption compound if inner layer adsorption occurs. The Mulliken population and density of state analysis demonstrate that the ionic properties of Fe-Os in the inner layer adsorption... [more]
The Numerical Analysis of Non-Newtonian Blood Flow in a Mechanical Heart Valve
Aolin Chen, Adi Azriff Basri, Norzian Bin Ismail, Kamarul Arifin Ahmad
February 17, 2023 (v1)
Keywords: Computational Fluid Dynamics, mechanical heart valve, non-Newtonian viscosity model, wall shear stress
Background: The non-physiological structure of mechanical heart valves (MHVs) affects the blood flow field, especially the complex microstructure at the hinge. Numerous studies suggest that the blood flow field in the aortic area with an MHV can be considered Newtonian. However, the Newtonian assumption is occasionally unreasonable, where blood viscosity changes with shear rate, exhibiting non-Newtonian shear-thinning characteristics. Methods: In this research, a comprehensive study of the non-Newtonian effects on the hemodynamic behavior of MHVs was performed. The impact of the Newtonian hypothesis was investigated on the internal hemodynamics of MHVs. Several non-Newtonian and Newtonian models were used to analyze the chamber flow and blood viscosity. MHVs were modeled and placed in simplified arteries. After the unstructured mesh was generated, a simulation was performed in OpenFOAM to analyze its hemodynamic parameters. Results: In the study of the non-Newtonian viscosity model, th... [more]
Assessing Long-Term Medical Remanufacturing Emissions with Life Cycle Analysis
Julia A. Meister, Jack Sharp, Yan Wang, Khuong An Nguyen
February 17, 2023 (v1)
Subject: Environment
Keywords: carbon footprint, greenhouse gas emissions, Life Cycle Analysis, medical remanufacturing, single-use devices
The unsustainable take-make-dispose linear economy prevalent in healthcare contributes 4.4% to global Greenhouse Gas emissions. A popular but not yet widely-embraced solution is to remanufacture common single-use medical devices like electrophysiology catheters, significantly extending their lifetimes by enabling a circular life cycle. To support the adoption of catheter remanufacturing, we propose a comprehensive emission framework and carry out a holistic evaluation of virgin manufactured and remanufactured carbon emissions with Life Cycle Analysis (LCA). We followed ISO modelling standards and NHS reporting guidelines to ensure industry relevance. We conclude that remanufacturing may lead to a reduction of up to 60% per turn (−1.92 kg CO2eq, burden-free) and 57% per life (−1.87 kg CO2eq, burdened). Our extensive sensitivity analysis and industry-informed buy-back scheme simulation revealed long-term emission reductions of up to 48% per remanufactured catheter life (−1.73 kg CO2eq).... [more]
Effect of Pouch Size on Sterilization of Ready-to-Eat (RTE) Bracken Ferns: Numerical Simulation and Texture Evaluation
Hwabin Jung, Yun Ju Lee, Won Byong Yoon
February 17, 2023 (v1)
Keywords: bracken fern, heat transfer simulation, home meal replacement, sterilization, texture of cooked vegetable
Bracken fern (Pteridium aquilium, BF) is a widely consumed vegetable. It has the potential to be manufactured as a ready-to-eat (RTE) product as a cooking ingredient and a side dish. The aim of the current study was to develop sterilized BF RTE products and to investigate textural qualities depending on the size of the pouches. The F0-value at the cold point according to pouch size (100, 150, and 200 g) targeted at 15 min was determined through heat transfer simulation using the calibrated heat transfer coefficient. The location of the cold points in the stand-up pouches was moved upward from the bottom of the pouch by increasing the pouch size. The sterilization time for 100, 150, and 200 g was evaluated as 35.0, 41.5, and 47.5 min, respectively. The textural properties measured using the cutting test showed significant differences according to the location in the pouch. The textural degradation of BF in the top part of the pouch was more extensive than that at the bottom due to the s... [more]
Developing Trusted IoT Healthcare Information-Based AI and Blockchain
Rayed AlGhamdi, Madini O. Alassafi, Abdulrahman A. Alshdadi, Mohamed M. Dessouky, Rabie A. Ramdan, Bassam W. Aboshosha
February 17, 2023 (v1)
Keywords: blockchain, deep learning, Internet of Things (IoT), smart healthcare systems, transfer learning
The Internet of Things (IoT) has grown more pervasive in recent years. It makes it possible to describe the physical world in detail and interact with it in several different ways. Consequently, IoT has the potential to be involved in many different applications, including healthcare, supply chain, logistics, and the automotive sector. IoT-based smart healthcare systems have significantly increased the value of organizations that rely heavily on IoT infrastructures and solutions. In fact, with the recent COVID-19 pandemic, IoT played an important role in combating diseases. However, IoT devices are tiny, with limited capabilities. Therefore, IoT systems lack encryption, insufficient privacy protection, and subject to many attacks. Accordingly, IoT healthcare systems are extremely vulnerable to several security flaws that might result in more accurate, quick, and precise diagnoses. On the other hand, blockchain technology has been proven to be effective in many critical applications. Bl... [more]
Scenario-Driven Methodology for Cascading Disasters Risk Assessment of Earthquake on Chemical Industrial Park
Li Guo, Junming Liang, Tao Chen, Yuan Gao, Zhen Yang
February 17, 2023 (v1)
Keywords: cascading disasters, cross-impact analysis (CIA) model, damping interpretation structural model (DISM), earthquake
With the increase in industrial accidents induced by natural disasters, the study of earthquake risk assessment has been widely considered by scholars. However, the cascade evolution of Natech (natural−technological) disasters has not been thoroughly studied, especially in chemical parks with complex technological processes. From the perspective of scenario deduction, combined with cross-impact analysis and a damping interpretation structural model, this paper analyzes the evolution process of cascade disaster in a chemical industrial park after the Wenchuan earthquake. At the same time, a visual network risk assessment model is constructed to identify the impact of earthquake cascade disasters on the park. The simulation results show that the scenario-driven risk assessment method proposed in this paper can directly reflect the coupling relationship and propagation path among the derived events and realize dynamic, intuitive and structured disaster expression to deal with the earthqua... [more]
CFD Analysis of Mixing Process of Detergents in Rotational and Displacement Vessels
Jerónimo Domingo, Alfredo Iranzo, David Arnanz, Akhilesh K. Srivastava, Michael Groombridge, Jared Hansen
February 17, 2023 (v1)
Keywords: CFD simulation, detergent mixing, response surface for digital twin
As part of the European Commission research project DIY4U focused on the development of machinery to be installed in supermarket allowing customers to define their customized detergent according to their needs. These machines will mix the detergent components (surfactant, fatty acid, water, perfume, etc.) already in the detergent canister as sold to consumers. To avoid long waiting times for customers, and to obtain a product with good quality and consistency, mixing must be very efficient. A mixing process with rotation and displacement by means of rotating the canister around an axis below the canister bottom has been checked by means of Computational Fluid Dynamics (CFD) tools after validation of one case with lab results. This is a new approach for liquid detergents, as commonly is a powder detergent production process. The mixing process has been simulated for 39 different combinations of components mass fraction percentages and the mixing quality observed during the mixing period... [more]
Aqueous Two-Phase Systems Based on Ionic Liquids and Deep Eutectic Solvents as a Tool for the Recovery of Non-Protein Bioactive Compounds—A Review
Filipe Smith Buarque, Gabrielle Victoria Gautério, Maria Alice Zarur Coelho, Ailton Cesar Lemes, Bernardo Dias Ribeiro
February 17, 2023 (v1)
Subject: Biosystems
Keywords: alkaloids, bioseparation, green processes, natural pigments, phenolic compounds
Aqueous two-phase systems (ATPS) based on ionic liquids (IL) and deep eutectic solvents (DES) are ecofriendly choices and can be used to selectively separate compounds of interest, such as bioactive compounds. Bioactive compounds are nutrients and nonnutrients of animal, plant, and microbial origin that benefit the human body in addition to their classic nutritional properties. They can also be used for technical purposes in food and as active components in the chemical and pharmaceutical industries. Because they are usually present in complex matrices and low concentrations, it is necessary to separate them in order to increase their availability and stability, and ATPS is a highlighted technique for this purpose. This review demonstrates the application of ATPS based on IL and DES as a tool for recovering nonprotein bioactive compounds, considering critical factors, results and the most recent advances in this field. In addition, the review emphasizes the perspectives for expanding t... [more]
Microbial Natural Products with Wound-Healing Properties
Prima F. Hillman, Chaeyoung Lee, Sang-Jip Nam
February 17, 2023 (v1)
Subject: Biosystems
Keywords: microbial-derived compounds, natural products, wound-healing
Wound healing continues to pose a challenge in clinical settings. Moreover, wound management must be performed properly and efficiently. Acute wound healing involves multiple cell divisions, a new extracellular matrix, and the process of formation, such as growth factors and cytokines, which are released at the site of the wound to regulate the process. Any changes that disrupt the healing process could cause tissue damage and prolong the healing process. Various factors, such as microbial infection, oxidation, and inflammation, can delay wound healing. In order to counter these problems, utilizing natural products with wound-healing effects has been reported to promote this process. Several natural products have been associated with wound healing, most of which are from medicinal plants. However, secondary microbial metabolites have not been extensively studied for their wound-healing properties. Further, investigations on the wound-healing control of natural microbial products are re... [more]
The Effect of Low Positive Temperatures on the Formation of Secondary Metabolites in Rhodiola quadrifida (Pall.) Fisch. et C.A. Mey. In Vitro Cultures
Anna Y. Stepanova, Evgeny A. Gladkov, Dmitry V. Tereshonok, Renat N. Selimov, Elisaveta N. Goncharova, Aleksandra I. Solov’eva
February 17, 2023 (v1)
Subject: Biosystems
Keywords: callus, hairy roots, Rhodiola quadrifida, rosarin, rosavin, rosin, salidroside, tyrosol
Global warming is one of the most serious problems leading to changes in the distribution areas of species and biodiversity. Rhodiola quadrifida is a rare plant with adaptogenic properties and grows in the highlands in a narrow temperature range of 2−15 °C. The aim of our work was to study the growth and content of the main metabolites in two in vitro cultures of Rhodiola quadrifida at temperatures of 5, 15 and 25 °C. Hairy roots and calli were cultivated on agar medium for 28 days. The maximum values of the growth index were observed at 25 °C (2.32 and 2.12 for calli and hairy roots, respectively). HPLC-MS showed the absence of tyrosol and rosarin in both cultures, and rosin in the root culture. The content of salidroside changed slightly in calli and roots. Cultivation at 5 °C significantly stimulated the formation of rosin in calli. Only a residual amount of rosavin was noted in the roots, regardless of temperature. The content of rosin was higher in calli at 15 °C with a maximum co... [more]
Path Planning of Mobile Robots Based on an Improved Particle Swarm Optimization Algorithm
Qingni Yuan, Ruitong Sun, Xiaoying Du
February 17, 2023 (v1)
Keywords: differential evolution algorithm and self-adaption, Particle Swarm Optimization, path planning
Aiming at disadvantages of particle swarm optimization in the path planning of mobile robots, such as low convergence accuracy and easy maturity, this paper proposes an improved particle swarm optimization algorithm based on differential evolution. First, the concept of corporate governance is introduced, adding adaptive adjustment weights and acceleration coefficients to improve the traditional particle swarm optimization and increase the algorithm convergence speed. Then, in order to improve the performance of the differential evolution algorithm, the size of the mutation is controlled by adding adaptive parameters. Moreover, a “high-intensity training” mode is developed to use the improved differential evolution algorithm to intensively train the global optimal position of the particle swarm optimization, which can improve the search precision of the algorithm. Finally, the mathematical model for robot path planning is devised as a two-objective optimization with two indices, i.e.,... [more]
Encapsulation of Formosa Papaya (Carica papaya L.) Seed Extract: Physicochemical Characteristics of Particles, and Study of Stability and Release of Encapsulated Phenolic Compounds
Mércia da Silva Mesquita, Priscila Dayane de Freitas Santos, Augusto Tasch Holkem, Marcelo Thomazini, Carmen Silvia Favaro-Trindade
February 17, 2023 (v1)
Keywords: antioxidants, digestibility, maltodextrin, microcapsules, phenolics, stability
Papaya seeds are a promising source of phenolic compounds, but these are unstable, and the papaya extract has a bitter taste. This study aimed to encapsulate papaya seed extracts at different maturation levels, and to characterize the obtained microparticles for their physicochemical properties, chemical stability and release of bioactives. Extracts of papaya (unripe and ripe) seeds were spray-dried using concentrations of 0, 15 and 30% of maltodextrin and inlet air temperatures of 130 and 150 °C. The powders were analyzed for yield, moisture, Aw, hygroscopicity, dispersibility, color parameters, morphology, mean diameter, total phenolics, antioxidant activity, stability during storage and release of phenolics in simulated gastrointestinal fluids. Powders produced with maltodextrin showed better results regarding particle diameter, hygroscopicity, dispersibility, and phenolic stability during storage. All powders showed antioxidant action and significant values of total phenolic compou... [more]
Special Issue on “Biodiesel Production Processes and Technology”
Juan Francisco García Martín, Miguel Torres García, Paloma Álvarez Mateos
February 17, 2023 (v1)
Raw oils and fats cannot be directly used in modern diesel engines, as their viscosity is too high [...]
Using Photogrammetry to Obtain 3D-Printed Positive Foot Casts Suitable for Fitting Thermoconformed Plantar Orthoses
Ana María Pérez Pico, Félix Marcos Tejedor, Luis Carlos de Cáceres Orellana, Pablo de Cáceres Orellana, Raquel Mayordomo
February 17, 2023 (v1)
Subject: Biosystems
Keywords: 3D photography, 3D printed, additive manufacture, foot orthoses, photogrammetry, positive cast
The use of photogrammetry provides an inexpensive, alternative method that can simplify the processes traditionally carried out in the orthotics workshop. The objectives of this study are to develop a method based on photogrammetry to obtain 3D-printed positive foot casts for fabricating thermoconformed orthoses from a negative cast in phenolic foam. Using a basic Smartphone, a photo capture protocol for feet, free software and a 3D printer, we tested the suitability of the positive cast obtained to fabricate custom foot orthoses using thermoconformed 3 mm polypropylene in the orthotics laboratory. The results show that digitally fabricated casts provide a very close replicate of the positive casts obtained traditionally through plaster casting (maximum dimension discrepancy between casts of 2 mm in length and 0.4 mm in forefoot, midfoot and rearfoot measurements). They are also suitable for the process of fabricating 2- and 3-mm polypropylene thermoconformed plantar orthoses. Photogra... [more]
Real-Time Cell Growth Control Using a Lactate-Based Model Predictive Controller
Kathleen Van Beylen, Janne Reynders, Ahmed Youssef, Alberto Peña Fernández, Ioannis Papantoniou, Jean-Marie Aerts
February 17, 2023 (v1)
Keywords: cell expansion, cell-based therapies, lactate, real-time model predictive control
Providing a cost-efficient feeding strategy for cell expansion processes remains a challenging task due to, among other factors, donor variability. The current method to use a fixed medium replacement strategy for all cell batches results often in either over- or underfeeding these cells. In order to take into account the individual needs of the cells, a model predictive controller was developed in this work. Reference experiments were performed by expanding human periosteum derived progenitor cells (hPDCs) in tissue flasks to acquire reference data. With these data, a time-variant prediction model was identified to describe the relation between the accumulated medium replaced as the control input and the accumulated lactate produced as the process output. Several forecast methods to predict the cell growth process were designed using multiple collected datasets by applying transfer function models or machine learning. The first controller experiment was performed using the accumulated... [more]
A Novel Design towards Reducing Leakage Loss for Variable Geometry Turbines
Kai Zhou, Xinqian Zheng
February 17, 2023 (v1)
Keywords: leakage loss, low-pressure turbine, variable geometry turbine
To accommodate the next generation of adaptive/variable cycle engines and gas turbine power, the variable geometry turbine (VTG) is widely acknowledged as a most essential component. VGT consists of an adjustable vane to address the combined goals of high dry thrust and low specific fuel consumption (SFC) at subsonic cruises for aero-engines. This concept allows an engine to operate at a constant bypass ratio over a wide range of pressure ratios. To avoid scraping during rotation for guide vanes, a typical gap is deliberately left, which leads to significant leakage loss. In this research work, a novel spherical convex plat with a pivot shaft is proposed, which can be obtained by additive manufacturing. The plat is sophisticatedly designed according to the aggressive tip/hub pressure gradient. This design naturally generates a blockage for the gas from the pressure side towards the suction side. As a result, the most aggressive pressure gradient is removed, and maximum leakage flow is... [more]
Current Challenges in the Sustainable Valorisation of Agri-Food Wastes: A Review
Cristina V. Berenguer, Carolina Andrade, Jorge A. M. Pereira, Rosa Perestrelo, José S. Câmara
February 17, 2023 (v1)
Subject: Biosystems
Keywords: agri-food waste, bioactive compounds, food loss, food waste, minerals, potential applications, valorisation
In the upcoming years, the world will face societal challenges arising, in particular, from the impact of climate change and the inefficient use of natural resources, in addition to an exponential growth of the world population, which according to the United Nations (UN) estimations will be 9.8 billion in 2050. This increasing trend requires optimized management of natural resources with the use of value-added waste and a significant reduction in food loss and food waste. Moreover, the recent pandemic situation, COVID-19, has contributed indisputably. Along with the agri-food supply chain, several amounts of waste or by-products are generated. In most cases, these biomass wastes cause serious environmental concerns and high costs to enterprises. The valorisation of the agri-food loss and food industry wastes emerged as a useful strategy to produce certain value-added compounds with several potential applications, namely in the food, health, pharmaceutical, cosmetic, and environmental f... [more]
Case Study: Successful Application of a Novel Gas Lift Valve in Low Pressure Wells in Fuling Shale Gas Field
Qiaoping Liu, Jingfei Tang, Wenqi Ke, Haibo Wang, Uzezi Davis Orivri
February 17, 2023 (v1)
Keywords: gas lift, low pressure, piping line, shale gas
The Fuling shale gas field is facing a rapid gas production decline due to heavy liquid loading issues. Given the condition that most wells are located at remote areas in the mountains, the traditional gas lift methods that require either fixed compressor or skid-mounted gas lift trucks do not seem feasible and occur high operation costs. A new type of gas lift valve that can be opened or closed at a low valve dome pressure indicates the high sensitivity to low production pressure. Thus, the piping line pressure can be utilized to activate the valve due to its new advantages. In addition, the specially designed structure of the gas lift valve can be activated via pressure increases in the tubing to create a channel between the tubing and annulus. The valve that previously functioned as a dummy valve was then switched to a gas lift valve. Field application results show that all wells were successfully restarted by only utilizing the low piping pressure, and loaded liquid was lifted with... [more]
Renewable Power and Heat for the Decarbonisation of Energy-Intensive Industries
Alessandro A. Carmona-Martínez, Alejandro Fresneda-Cruz, Asier Rueda, Olgu Birgi, Cosette Khawaja, Rainer Janssen, Bas Davidis, Patrick Reumerman, Martijn Vis, Emmanouil Karampinis, Panagiotis Grammelis, Clara Jarauta-Córdoba
February 17, 2023 (v1)
Keywords: Biomass, decarbonisation, energy-intensive industries, geothermal, green hydrogen, heat pumps, renewable energies, Solar Thermal
The present review provides a catalogue of relevant renewable energy (RE) technologies currently available (regarding the 2030 scope) and to be available in the transition towards 2050 for the decarbonisation of Energy Intensive Industries (EIIs). RE solutions have been classified into technologies based on the use of renewable electricity and those used to produce heat for multiple industrial processes. Electrification will be key thanks to the gradual decrease in renewable power prices and the conversion of natural-gas-dependent processes. Industrial processes that are not eligible for electrification will still need a form of renewable heat. Among them, the following have been identified: concentrating solar power, heat pumps, and geothermal energy. These can supply a broad range of needed temperatures. Biomass will be a key element not only in the decarbonisation of conventional combustion systems but also as a biofuel feedstock. Biomethane and green hydrogen are considered essenti... [more]
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