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A Comparative Evaluation of Dark Fermentative Bioreactor Configurations for Enhanced Hydrogen Production
No full textEnergy from renewable resources has been growing in popularity, which ultimately helps reduce emissions of greenhouse gases (GHGs) and contaminants. Since hydrogen (H2) has a higher combustion production of energy than hydrocarbon fuels, it has been identified as a clean, sustainable, and environmentally friendly energy source. There are several benefits to producing biohydrogen (bioH2) from renewable sources, including lower cost and increased sustainability. Among the bioH2 production processes, dark fermentation supports commercialization and scale-up for industrial applications. This paper considers the various bioreactors, such as anaerobic sequencing batch, continuous stirred, up-flow, fixed-bed, and membrane reactors, and their operational approaches for bioH2 production. This review paper also performs the bibliometric analysis method to identify historical and current developments in a particular field of reactor configuration studies. Furthermore, the main variables influencing reactor performance and methods for increasing process efficiency considering economic and environmental aspects are addressed. The results revealed that continuously stirred reactors are widely utilized for bioH2 production as a cost-effective reactor configuration. Moreover, the membrane bioreactors and fixed-bed reactors are yielded higher bioH2 performance than other configurations. Nevertheless, high energy consumption and costs have presented the need for further development of reactors. Consequently, future recommendations to solve the critical problems faced in reactor configurations, the gaps in the literature, and the points that need improvement were comprehensively reported. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025
Euler–Euler Numerical Model for Transport Phenomena Modeling in a Natural Circulation Loop Operated by Nanofluids
No full textThis paper explores a computational approach to model multiphase heat transfer and fluid flow in a natural circulation loop utilizing nanofluids. We propose and implement an Euler–Euler framework in a CFD environment, incorporating an innovative boundary condition to preserve mass conservation during thermophoretic particle flux. The model’s accuracy is verified through a one-dimensional example, by comparing results against both an Euler–Lagrange model and an in-house finite volume solution. Experimental validation is conducted with aluminum oxide nanofluids at varying nanoparticle concentrations. We prepared the nanofluids and measured their thermophysical properties up to 60∘C. We assess the thermal performance of the nanofluid in natural circulation loop at different heating powers via experiment and numerical simulations. The findings reveal that the heat transfer enhancement offered by the nanofluid is modest, with minimal differences observed between the proposed Euler–Euler approach and a simpler single-phase model. The results underscore that while the Euler–Euler model offers detailed particle–fluid interactions, its practical thermal advantage is limited in this context. © The Author(s) 2025
A Review on Adaptive and Non-Adaptive Shading Devices for Sustainable Buildings
No full textAdaptive and non-adaptive shading devices are noteworthy fa ; ccedil;ade components in designing sustainable buildings. As the comparisons of their characteristics are limited, it becomes challenging to understand their efficiency, including their impacts on occupant behavior and comfort metrics. This comprehensive review covers (a) identifying the relationship between architectural parameters and performance targets, (b) exploring model development techniques due to performance targets, and (c) declaring both energy and visual comfort metrics. The paper covers 103 papers under architectural parameters and their corresponding performance targets, namely, daylight and visual comfort metrics with lighting energy. The aim is to identify existing research trends, methodological gaps, and potential for future study by examining how performance targets affect model development approaches. The categorizations include design parameters (shading elements and fa ; ccedil;ade organization), control systems (shading device control, artificial lighting control, integrated systems), performance targets (daylight metrics, visual comfort metrics, lighting energy metrics), and modeling methods (simulation, experimental, optimization). Results showed that few studies combined daylight, visual comfort, and lighting energy due to complex modeling approaches, whereas most studies dealt only with daylight. With the increase in simulation software used to conduct research results on various focuses, an increasing trend in published papers is available in this field. Studies mostly observed changes in shading device typologies, slat angles, and numbers. The most dominant climate types were humid subtropical (Cfa) and Mediterranean (Csa). Future studies can be directed to integrated performance targets and combine suitable modeling approaches with AI technologies to produce more validated and accurate results
An Improved Pointing Error Model for Mmwave and Thz Links: Antenna and Array Design Impact
No full textPointing error has a significant impact on the performance of millimeter wave (mmWave) and terahertz (THz) communications due to directional transmission. Currently existing pointing error models are lacking in capturing the mmWave/THz radiation characteristics and/or the impact of antenna design and array design. Therefore, in this letter, a simple analytical pointing error model for highly directional mmWave/THz transmission is proposed. By utilizing the Gaussian beam approximation for both the array element radiation pattern and the array factor, the presented model incorporates antenna design parameters (maximum gain and 3 dB beamwidth) and array design parameters (number of array elements, element spacing, and 3 dB beamwidth). This approximation is validated via electromagnetic simulations in CST Microwave Studio. Afterwards, the statistics of the pointing error are derived according to the Gaussian beam approximation, and it is demonstrated that the pointing error follows a special case of the negative log-Gamma distribution with the shape parameter of 2 and the scale parameter depending on antenna/array design and jitter variance. It is shown that the proposed model aligns perfectly with the simulation results. Moreover, the outage performance of an aerial communication scenario is analyzed to examine the impact of pointing errors. The results have revealed that the antenna and array design parameters are as influential as the jitter variance, and they cannot be neglected
High Accuracy and Applicability Battery Aging Models for Electric Vehicle Applications
No full textBatteries have gained significant attention due to their numerous advantages in applications such as electric vehicles. One of the factors limiting industry adoption is the aging of batteries. The characteristics of battery aging vary depending on many factors such as battery type, electrochemical reactions and operating conditions. Here we document the comparison of semi-empirical aging models (SEM), highlighting limitations and challenges. In addition, four SEMs are proposed. The usability and compatibility of these models are evaluated using experimental data from various sources including the Horizon 2020 Helios Project. The optimized parameters of each model are documented via linear regression and genetic algorithms. The results show that the genetic algorithm approach provides higher accuracy in comparison to the linear regression. The documented SEMs reveal better prediction performance than the literature of calendar obsolescence with SEM-3 and 7 performing particularly well in predicting capacity loss for the Helios dataset with low errors, i.e. 0.43 and 0.79 RMSE, respectively. The range of RMSE values for model predictions across all the datasets ranges from 0.196 to 3.903. This study aims to document the accuracy of SEMs both from the literature and proposed in the paper relative to battery ageing data from distinct sources
Performance Improvement of Carbon Fiber-Reinforced Abs Composites by Introducing Fullerene Nanoparticles
No full textRecently, polymer composites have been extensively researched in industrial fields such as electrical conductance, ohmic heating, electromagnetic shielding and electrostatic discharge, particularly in engineering polymers reinforced with carbonaceous additions. Herein, fullerene (C60) and short carbon fiber (CF) were incorporated with acrylonitrile-butadiene-styrene copolymer (ABS) using melt-compounding followed by an injection-molding process. Composite samples were produced with contents of 20 wt% of CF besides 0.1, 0.5 and 1.0 wt% of C60. Tensile, impact, hardness and wear tests, conductive atomic force microscopy, dynamic mechanical analysis, thermogravimetric analysis, melt flow index tests and scanning electron microscopy (SEM) were performed to characterize mechanical, electrical, thermomechanical, thermal, melt-flow and structural behaviors of ABS-based composites involving CF and C60. Based on the mechanical test findings obtained for the developed composites, comprising tensile and impact test results, C60 additions contributed to a significant rise in tensile strength and impact resistance of CF-reinforced ABS composites, with a 20% increase in tensile resistance being achieved by introduction C60 into the ABS/CF structure. C60 addition enhanced efficiency by 50% in terms of tensile modulus. Electrical conductivity measurements confirmed that C60 nanoparticles and CF exhibited a synergy. The optimum synergistic ratio of C60/CF was obtained as 0.5/20. The conductive path in the ABS/CF composite system was established by incorporating C60 with different loading amounts. SEM micrographs of composites demonstrated that C60 nanoparticles were dispersed homogeneously into the ABS matrix involving lower amounts of C60. (c) 2025 The Author(s). Polymer International published by John Wiley ; Sons Ltd on behalf of Society of Chemical Industry
Recent Developments in the Treatment of Leishmaniasis: Natural Compounds, Drug Targets, in Silico Molecular Docking Approaches, and Nanocarriers
No full textLeishmaniasis is a common tropical disease caused by Leishmania protozoa. It affects 0.9 to 1.6 million people, causing 20,000–30,000 deaths annually. There are no effective vaccines, and current treatments have severe side effects. Drug resistance is a major obstacle in treating leishmaniasis. The necessity of drug discovery is indisputable. Natural compounds are promising candidates for drug discovery studies because of their diverse chemical structures and bioactivities. Experimental screening of compound libraries imposes high costs and is time-consuming. The molecular docking approach is beneficial for exploring new therapeutics in silico as it allows the screening of millions of drug candidates. Even if new drug candidates are discovered, delivery of the active ingredient to the target remains controversial. Nanocarriers are promising nanosystems that can address the drawbacks of drug delivery. This chapter focuses on natural compounds as drug candidates, targets, in silico drug discovery, and drug delivery for the treatment of leishmaniasis. © 2025 Elsevier Inc
Wnt/β-catenin Signaling in Central Nervous System Regeneration
No full textThe Wnt/β-catenin signaling pathway plays a pivotal role in the development, maintenance, and repair of the central nervous system (CNS). This chapter explores the diverse functions of Wnt/β-catenin signaling, from its critical involvement in embryonic CNS development to its reparative and plasticity-inducing roles in response to CNS injury. We discuss how Wnt/β-catenin signaling influences various CNS cell types-astrocytes, microglia, neurons, and oligodendrocytes-each contributing to repair and plasticity after injury. The chapter also addresses the pathway's involvement in CNS disorders such as Alzheimer's and Parkinson's diseases, psychiatric disorders, and traumatic brain injury (TBI), highlighting potential Wnt-based therapeutic approaches. Lastly, zebrafish are presented as a promising model organism for studying CNS regeneration and neurodegenerative diseases, offering insights into future research and therapeutic development. © 2024. The Author(s), under exclusive license to Springer Nature Switzerland AG
Efficiency Evaluation of Optimal Tlcd and Tmd for the Seismic Response Reduction of Buildings Considering Soil-Structure Interaction Effect
No full textTuned Mass Dampers (TMDs) and Tuned Liquid Column Dampers (TLCDs) are widely recognized passive vibration control devices used to reduce structural vibrations. While TMDs have been extensively studied for mitigating the seismic responses of multi-story buildings considering Soil-Structure Interaction (SSI), the efficiency of TLCDs in these conditions remains largely unexplored. Furthermore, a direct comparison of these devices under similar conditions has not been conducted. Then, to address these gaps, this study investigates the efficiency of TLCDs and compares them to TMDs in reducing seismic-induced vibrations, focusing on the influence of SSI. The control performance of both devices depends on various parameters, primarily the frequency and damping ratios. Therefore, the Mouth Brooding Fish (MBF) metaheuristic algorithm is applied to optimize these parameters, accounting for SSI effects. To evaluate the different efficiency between TMDs and TLCDs under SSI conditions, three types of shear buildings are considered: an eight-story, a sixteen-story and a forty-story structure. The seismic responses of the uncontrolled, TMD-controlled, and TLCD-controlled buildings are examined under twenty-two far-field and fourteen near-field earthquakes, considering both fixed-base and flexible-base scenarios. Results indicate that while both devices significantly reduce seismic responses, TMDs generally outperform TLCDs, particularly in taller buildings where the impact of SSI is more significant. Further, this study highlights that neglecting SSI in the design of these devices may lead to an overestimation of their effectiveness, especially in softer soils, emphasizing the importance of considering SSI in the optimization process for accurate and reliable outcomes
Formation and Stability of Hydrides During Hydrogenation of Ndfeb Magnets
No full textDemand for magnetsMagnets has increased in the last decades due to their usage in the energy sector. One of the most common magnetsMagnets used for applications such as electronic devices, wind turbines, etc. is Nd2Fe14B (NdFeB). NeodymiumNeodymium (Nd) is one of the critical elements listed by the EU, hence the efficient use and proper recyclingRecycling of Nd-containing materials become of great interest. Hydrogen is commonly used during magnetMagnets production and some hydrogen-assisted recyclingRecycling approaches were also reported. This study reports an analysis of formed hydridesHydrides during hydrogenationHydrogenation of NdFeB magnetsMagnets at up to 400 °C. In addition to experimental results, thermochemical modelingThermochemical modeling was performed by using FactSageFactSage databases to discuss the effect of temperature and pressure on hydrogenationHydrogenation. The study showed that the stability of phases changes with the temperature and pressure which affects the hydrogen content of phases after hydrogenationHydrogenation. © The Minerals, Metals ; Materials Society 2025