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 main research directions. The vortex-induced vibration transition mechanism of particle flow in complex restricted pipelines, as well as the improvement of signal processing algorithms and a better design of anti-spin/vortex elimination devices, continue to draw attention. The relevant result can offer a helpful reference for fluid-induced vibration detection and provide a technical solution for hydropower energy conversion. Full article

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 concentration distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 12.9% to 5.3%. This paper can provide a valuable reference with practical implications for subsequent research. Full article

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. Although the latest design has a wider spread of RTD, the conical design has shown promising results compared with a cylindrical drying chamber in terms of overall wall deposition behaviours. Full article

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. Full article

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 O_u (deprotonated upright hydroxyl) site, where it generates a monodentate adsorption compound, and to the O_l and O_u (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-O_s in the inner layer adsorption compound are reduced and Fe-O_s bonds are filled with strong bonding and weak antibonding orbitals. More chemical bonds are formed in the bidentate adsorption compound, and the bidentate adsorption has lower adsorption energy. Therefore, in the process of inner layer adsorption, bidentate adsorption is more likely to occur. Full article

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, the Casson model differs significantly from the Newtonian model, resulting in a 70.34% higher wall shear stress. In the modified Cross and Carreau models, the non-Newtonian behavior can significantly simulate blood in the MHV at different stages during initial and intermediate deceleration. The narrowing of the hinge region in particular, has a significant impact on evaluating blood rheology. The low flow rate and high wall shear force at the hinge can cause blood cell accumulation and injury time, resulting in hemolytic thrombosis. Conclusion: The results exhibit that the Newtonian hypothesis underestimates the hemodynamics of MHVs, whose complex structure leads to increased recirculation, stagnation, and eddy current structure, and a reasonable choice of blood viscosity model may improve the result accuracy. Modfied Cross and Carreau viscosity models effectively exhibit the shear-thinning behavior in MHV blood simulations. Full article

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 CO${}_2$eq, burden-free) and 57% per life (−1.87 kg CO${}_2$eq, 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 CO${}_2$eq). Our comprehensive results encourage the adoption of electrophysiology catheter remanufacturing, and highlight the importance of estimating long-term emissions in addition to traditional emission metrics. Full article

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 smaller dimensions. In addition, the percentage of textural degradation in the top part increased with increasing pouch sizes. The methods introduced in this study can be applied to validate the degree of sterilization and the texture of various stalk vegetables used for ready-to-eat products packed in stand-up pouches. Full article

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. Blockchain technology combined with IoT can greatly improve the healthcare industry’s efficiency, security, and transparency while opening new commercial choices. This paper is an extension of the current effort in the IoT smart healthcare systems. It has three main contributions, as follows: (1) it proposes a smart unsupervised medical clinic without medical staff interventions. It tries to provide safe and fast services confronting the pandemic without exposing medical staff to danger. (2) It proposes a deep learning algorithm for COVID-19 detection-based X-ray images; it utilizes the transfer learning (ResNet152) model. (3) The paper also presents a novel blockchain-based pharmaceutical system. The proposed algorithms and systems have proven to be effective and secure enough to be used in the healthcare environment. Full article

Electromagnetic braking (EMBr) technology, as one of the most effective technologies in the continuous casting process, provides an effective tool for improving the internal and external defects of steel products. Specifically, the EMBr technology takes the benefit of the generation of Lorentz force to decrease flow instability, mold powder entrapment, and surface defects, if applied properly. For this purpose, to gain a clear understanding of the effect of EMBr technology on the continuous casting process, a commonly used EMBr technology, namely ruler EMBr technology, is applied in the current work to investigate the dynamic behaviors of molten steel flow and steel–slag interface fluctuation inside a slab mold. Furthermore, to obtain a desirable braking effect of the ruler EMBr technology, operational parameters including the magnetic flux density, submerged entry nozzle (SEN) depth, and magnetic pole location are numerically investigated. The results demonstrate that the braking effect exerted by the ruler EMBr device is favorable for suppressing the impact of upward stream on the steel–slag interface with the magnetic flux density exceeding 0.3 T. For the influence of the SEN depth and magnetic pole location on the effect of ruler EMBr mold, the results show that a steady jet flow pattern can be obtained through the adjustment of a location between the ruler EMBr device and the SEN depth. For instance, when the ruler EMBr device installation position of 225 mm corresponds to the SEN depth of 150 mm, the upward deflection of jet stream is suppressed and a stable interface fluctuation profile is formed. With this adjustment, the possibility of mold flux entrapment is decreased. Full article

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 earthquake Natech (natural–technological) disaster scenario effectively and quickly. Full article

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 the use of nonconventional ATPS in purification systems, which consider the use of molecular modelling to predict experimental conditions, the investigation of diverse compounds in phase-forming systems, the establishment of optimal operational parameters, and the verification of bioactivities after the purification process. Full article

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 required due to a lack of studies. This review discussed the in vivo and in vitro research on the wound healing activities of natural microbial products, which may assist in the development of better wound treatments in the future. Full article

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. A response surface obtained from these simulations has been developed to be included in a Digital Twin, this being a task within this DIY4U project. The results show that this system is very efficient, taking a few seconds to develop a complete mixing. Also, the mixing time differences are quite small, requiring all customers to wait just few seconds independently of their detergent formulation. Full article

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 content at the end of the cultivation cycle 25 µg/g DW. Thus, Rhodiola quadrifida will be able to grow with an increase in temperature by 10 °C but this will be accompanied by a significant reduction in its medicinal value Full article