Artiles
Open Access
Article
13 June 2025Development of a Tailored Culture Medium for Improved De Novo Biosynthesis of Ferulic Acid in Fed-Batch Biphasic Fermentation with Saccharomyces cerevisiae
Ferulic acid (FA) is a natural phenolic compound with diverse biological properties, widely used in the food and cosmetic industries. Its production from fermentation is a promising strategy because its extraction from biomass is costly. To enable cost-effective microbial production, medium optimization is mandatory. In this study, we focused on applying a fed-batch biphasic strategy for the production of ferulic acid (FA) from d-glucose. FA production was first assessed in a classically defined medium, 2X Yeast Nitrogen Base (YNB) without amino acids, and complex Yeast Peptone Dextrose (YEPD) medium. Finally, as FA has deleterious antimicrobial properties, continuous extraction from the broth using fed-batch biphasic fermentation was implemented. Our results showed that YEPD medium resulted in the production of 207 mg·L−1 of FA in a medium composed of 30 g·L−1 d-glucose, 10 g·L−1 yeast extract, 1 g·L−1 (NH4)2SO4, 10 g·L−1 peptone, 4 g·L−1 KH2PO4 and 2 g·L−1 K2HPO4. Fed-batch biphasic fermentation system resulted in almost a two-fold increase in FA production compared to batch one (312.6 mg·L−1 and 176.7 mg·L−1, respectively) showing the importance of fed-batch biphasic fermentation and medium detoxification.
Open Access
Review
12 June 2025Research Progress and Key Technical Barriers in CaO/Ca(OH)2 Based Energy Storage: A Systematic Review
The CaO/Ca(OH)2 thermochemical energy storage system has garnered significant attention due to its cost-effectiveness, abundant raw material availability, optimal decomposition thermodynamics, high energy density, and recyclability as a promising candidate for large-scale renewable energy integration. Significant progress has been made in the research field of the CaO/Ca(OH)2 energy storage system, while there are still key issues that require further investigation. This comprehensive review summarizes recent advancements in CaO/Ca(OH)2 thermochemical energy storage systems, focusing on reaction mechanism and optimization through material engineering strategies, thermal-fluid dynamics in reactor configurations, cyclic degradation mechanisms under operational stresses, and scalability constraints in system integration. Persistent technical bottlenecks requiring resolution are discussed, particularly sintering-induced capacity decay and suboptimal heat transfer efficiency. The reactor design and optimization with advanced material modification techniques targeting enhanced stability are introduced as well. These discussions and derived suggestions provide a potential opportunity to bridge fundamental material science discoveries with engineering implementation for enabling deployment in stable utilization of renewable energy.
Open Access
Commentary
12 June 2025Bone Marrow Transplantation as a Future Therapeutic Strategy for Idiopathic Pulmonary Fibrosis: Lessons from Hematopoietic Aging
Idiopathic pulmonary fibrosis (IPF) is a fatal disease with limited therapeutic options. Lung transplantation is the only curative treatment, but it is rarely available due to a lack of suitable donors. In a recent publication in Science Immunology, Farhat et al. demonstrated that bone marrow transplantation from young donors alleviates fibrosis by restoring immune resolution in aged hosts in animal models. Aged hematopoietic cells exacerbate fibrosis through the persistence of inflammatory macrophages and impaired Treg-derived IL-10, highlighting bone marrow rejuvenation as a potential treatment strategy for IPF.
Open Access
Opinion
11 June 2025Reflections on Photocatalysis Progress Since the Inspiration of Prof. David Ollis in 1992
Why has photocatalysis not gained the wide-ranging commercial applications in environmental purification of air and water that seemed promising 30+ years ago since the first international conference on TiO2 photocatalytic purification and treatment of water in 1992? The primary reason lies in its low intrinsic efficiency. The progress of R&D to enhance this efficiency has been slow, possibly due to an incomplete understanding of the underlying mechanisms of photocatalysis. There is also the possibility that certain factors, with effects comparable to those of the band gap, significantly influence photocatalytic performance but remain underexplored. Additionally, challenges such as mass transfer limitations and surface contamination hinder the industrial application of photocatalysts. It may be time for scientists to reconsider and address the limitations and practical application scenarios of photocatalysis.
Open Access
Article
11 June 2025Effect of Post Rolling Strategies on Microstructure and Mechanical Properties of Martensitic Heat-Resistant Steel
Four different rolling strategies were applied to comparatively study the post-rolling process on the microstructure and high-temperature mechanical properties of a high-boron P92 martensitic heat-resistant steel. Both the characteristics of martensitic lath structures and the evolution of precipitation and texture states are illustrated. Their influence on mechanical properties was also discussed based on the recrystallization state, dislocation density, precipitation state, and also the activation tendency of slipping systems of the dominated texture component. Results revealed that the post-rolling process can significantly improve the plasticity of quenched P92 steel while leading to the reduction of strength simultaneously. However, a high reduction and post isothermal holding sample (HRH) shows the best high-temperature mechanical performance with a balanced tensile strength of 352 MPa and elongation of 33.6%. It is the enhanced precipitation strengthening, recrystallization refinement, and lower Schmid values of main texture components that contribute to the mechanical property improvement of the HRH sample.
Open Access
Review
11 June 2025Recent Advances in High-Temperature Properties of High-Entropy Alloys
High-temperature alloys are critical for advanced thermal components in aerospace and energy industries. Conventional alloys, which rely on a single principal element with limited alloying additions, often exhibit insufficient phase stability and rapid oxidation at extreme temperatures. In recent years, high-entropy alloys (HEAs) have emerged as revolutionary candidates for high-temperature applications, overcoming the limitations of conventional alloys through their unique multi-principal element design and exceptional performance. This review systematically examines the latest progress in HEAs’ key high-temperature properties: tensile properties, creep resistance, oxidation resistance, and phase stability. Research demonstrates that HEAs achieve remarkable mechanical properties at elevated temperatures through multiple mechanisms, such as lattice distortion effects, precipitation of ordered L12-structured phases, and refined grain boundary engineering. For instance, refractory HEAs like MoNbTaVW and Hf-Nb-Ti-V systems exhibit superior creep resistance at temperatures exceeding 1600 °C, outperforming traditional nickel-based superalloys. The slow diffusion of oxygen and the formation of multi-component oxide layers enhance the high-temperature oxidation resistance of high-entropy alloys. Additionally, HEAs display excellent phase stability under thermal exposure, driven by high configurational entropy and optimized microstructural designs, including nanoscale lamellar phases and coherent precipitates. Despite these advances, challenges remain in balancing mechanical strength with ductility, ensuring long-term durability under cyclic thermal-mechanical loads, and tailoring compositions for extreme service conditions. Future efforts should integrate machine learning, computational modeling, and high-throughput experiments to accelerate the discovery of novel HEA systems and validate their performance in practical applications. By addressing these challenges, HEAs are poised to revolutionize material solutions for next-generation aerospace engines, nuclear reactors, and high-efficiency energy systems.
Open Access
Article
10 June 2025Influence of Surface Waves—Von Karman Street Interaction on Bottom Sediments Transport in the Vicinity of a Wind Turbine Mast: Experimental and Theoretical Study
Cylindrical structures used in offshore energy production systems are subjected to various stresses and loads (waves and currents). Understanding the interactions between these cylindrical structures and bedforms is critical, as rapid changes in the bathymetry can expose and damage pile foundations and cables. The impact of a vertical cylinder on a sandy sedimentary bottom subjected to hydrodynamic currents and surface waves is experimentally and theoretically studied. Tests were carried out at the wave flume where patterns are produced. It is observed that patterns emerge due to a subcritical instability at the water-sand interface at the bottom. The characteristics of these patterns can be explained using the Swift-Hohenberg equation. Finally, the experimental results will be applied to the numerical model using the Swift-Hohenberg equation.
Open Access
Case Report
09 June 2025Acute Myocardial Infarction with Multiple Giant Coronary Artery Aneurysms in a Juvenile with Kawasaki Disease
Coronary artery aneurysm (CAA), the most risky late complication of Kawasaki disease (KD), is associated with severe adverse cardiac events, such as acute myocardial infarction (AMI), in young patients. Herein, we describe a 16-year-old boy who suffered from occasional angina attack after a recent myocardial infarction due to multiple giant CAAs during the asymptomatic period of KD. Coronary angiography (CAG) revealed multiple large CAAs of about 9 mm in diameter at the left anterior descending artery (LAD) and more than 12 mm at the left circumflex coronary artery (LCX). To optimize the management and reduce the morbidity and mortality of giant CAAs, it is imperative to consider antecedent KD at the earliest possible stage, particularly in young patients with angina pectoris or AMI but lacking traditional risk factors for atherosclerosis. Long-term follow-up with an electrocardiogram (ECG), echocardiogram, or coronary computed tomography angiography (CCTA) is essential and should not be overlooked. In addition, this case highlights the great significance of working out a more comprehensive and effective management strategy for such KD juveniles, including drugs, percutaneous coronary intervention (PCI) or even surgery.
Open Access
Article
09 June 2025High-Temperature Dielectric Energy Storage Materials Fabricated by Crosslinking Titanium Dioxide and Polyarylene Ether Nitrile
Dielectric materials have broad application prospects in the field of high-temperature electronic power systems. Up to now, high-temperature dielectric materials are mainly prepared by using high glass transition temperature (Tg) polymers. However, the incompatibility between polymers and fillers, which are incorporated for high energy density, leads to soaring dielectric losses at high temperatures, resulting in a nosedive of discharged energy density (Ud) and efficiency (η). In this paper, we report the fabrication of high-temperature dielectric materials via the self-crosslinking of phthalonitriles from phthalonitriles modified titanium dioxide (TiO2-2CN) and phthalonitriles terminated polyarylene ether nitrile (PEN-2CN). TiO2-2CN is firstly synthesized and characterized, then incorporated into PEN-2CN to prepare TiO2/PEN nanocomposites, which transform into TiO2-PEN hybrids afterwards. The fabricated TiO2-PEN hybrids are confirmed by the change of SEM sectional morphology, as well as the increase of their Tg and thermal decomposition temperature (Td). With the addition of TiO2-2CN, both the Tg, Td, and Ud of TiO2/PEN nanocomposites are improved. In addition, due to the formation of covalent bonds within TiO2-PEN, the hybrids exhibit excellent high-temperature dielectric energy storage performance. Specifically, at 150 °C, the Ud of 10 wt% TiO2-PEN is 0.60 J/cm−3, which is over 95% of that at RT. Moreover, η is greater than 90% and remains unchanged after 10,000 charge and discharge cycles. This method used for preparing TiO2-PEN hybrids through a self-crosslinking reaction of phthalonitriles provides a new approach for preparing high-temperature dielectric materials.
Open Access
Article
06 June 2025Effects of Changing the Specific Surface Area in the Ceramic Matrix of CAC-Containing Refractory Castables on the Initial Stiffening and Setting Behaviour
Besides the coarse and medium grain size distribution, the matrix components play a central role in the performance of refractory castables. Practical experience shows that the particle size distribution (PSD) and the specific surface area of the ceramic matrix significantly influence processing, setting, and sintering behaviour. However, there is a lack of systematic studies on how PSD or specific surface area changes affect castable properties. This study aims to address this gap by varying ceramic matrices to create refractory model castables with different matrix surface areas. Three dispersing agents with different mechanisms (electrosteric and steric) were used at graded concentrations. Results show that castables with higher specific surface areas (using (very) finely ground and highly sintered alumina raw materials with high specific surface areas) and different dispersing agents and their concentrations show substantial differences in the initial stiffening and setting behaviour. Higher specific surface areas of the matrix result in an earlier first stiffening, while adding more dispersing agents leads to delayed stiffening. The refractory model castables’ first stiffening and hydration range (with a simultaneous temperature maximum) vary considerably depending on the dispersing agent used and its concentration, caused by completely different mechanisms.
