Vol. 2 No. 3 (2024)

A high-performance, fish-friendly bulb turbine was developed in this study by optimizing a runner with spiral blades to enhance the flow passage for fish. The key aspect of this work is multi-objective optimization based on the orthogonal method. Four factors were focused on: the number of guide vanes, the wedge angle of the blades, the distance of vaneless space, and the pitch variation ratio. The optimal value of each design parameter was determined through comprehensive measurements, including intuitive analysis, range analysis, and synthetical frequency analysis. The evaluating indexes were unit output, efficiency, fish-passing damage rate, pressure fluctuation, maximum blade deformation, and equivalent stress. The results indicate that the pitch ratio parameter significantly affected hydraulic performance, while the number of guide vanes primarily influenced fish-passing performance. The optimized turbine achieved a hydraulic efficiency of 84.05%, with a fish damage rate of only 0.01%. Structurally, the vibration modes of the runner were mainly oscillating deformation, rotating deformation around the axis, and bending deformation. The difference between the hydraulic excitation frequencies and the natural frequencies of the runner exceeded 20%, ensuring no resonance under the best efficiency point (BEP) condition. The dry and the prestressed modals showed similar natural frequencies and vibration patterns for the runner, whereas the wet modal showed higher natural frequencies for the runner.

This article examined the effectiveness of bioclimatic strategies to enhance thermal comfort and decrease energy consumption in a desert-climate residence. The study assessed the impact of thermal insulation, natural ventilation, and phase-change materials (PCMs) over a year, with each strategy evaluated both independently and in combination. Monthly energy bills were analyzed to determine the impact of these strategies. The results indicated substantial reductions in energy costs, with decreases of up to 50% during transitional seasons; however, the complete elimination of heating and cooling systems was not feasible due to significant thermal phase differences between indoor and outdoor environments. Further analysis of thermal discomfort hours revealed that increasing insulation thickness during specific seasons could mitigate peak heat intensity and delay its occurrence, thus extending periods of comfort and reducing discomfort hours. Despite these improvements, some periods of thermal distress persisted during the warmest months, underscoring the necessity for a balanced approach to climate adaptation strategies. Overall, the implementation of these strategies proved effective in improving comfort and reducing energy usage in desert-climate homes, although they do not fully negate the need for traditional heating and cooling systems.

Hydrogen (H₂) plays a crucial role in the transformation of the energy structure due to its environmental friendliness, renewability and high energy density. The photocatalytic and electrocatalytic hydrogen evolution reaction (HER) presents a promising approach for H₂ production. Molybdenum disulfide (MoS₂) has emerged as a promising catalyst in photocatalytic and electrocatalytic HER due to its high activity, easy preparation and cheapness. However, it suffers from poor stability and inactive basal planes. In this review, we encapsulated the research advancements of MoS₂ for photocatalytic and electrocatalytic HER in the past ~10 years. The latest strategies to enhance the catalytic activity of MoS₂, such as doping, phase adjustment, surface modification and others, are also summarized. The relationship between structure and activity for enhanced H₂ generation by different means is briefly introduced. The challenges and directions of MoS₂ materials in photocatalysis and electrocatalysis for HER are also discussed, aiming to provide promising guidelines for future research.

The daily well-being of modern humanity is closely linked to the use of different devices operating through different sources of energy conversion. Electromagnetic energy obtained from the conversion of clean energy is one of the most used in devices in this context. The use of these devices reflects the expected results, often accompanied by unwanted side effects. These undesirable side effects correspond to the interaction of artificial electromagnetic radiation with living tissues of biodiversity (One Health concept). The corresponding living tissues are related to humans, animals (domestic and wild), birds, plants, etc., and more generally to biodiversity, including the ecosystem. Therefore, these harmful effects could be reduced by intelligent and sustainable construction and protection (Responsible Attitude concept) of these devices. This article aimed to illustrate the implication of the concepts of One Health and Responsible Attitude in the management of the daily use of wireless communication tools with electromagnetic energy, as well as power transfer devices. The two concepts were first discussed. The biological effects on living tissues due to exposure to electromagnetic field radiation were analyzed in the case of humans, animals and plants. The different characteristics of the radiated field and exposed tissues influencing these effects, as well as the governing laws and mathematical modeling of the effects, were examined. Additionally, the means for protecting living tissues from electromagnetic radiation were inspected. The analyses pursued in this article were supported by examples taken from the literature.

Utilizing synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) to capture intermediates has significantly enhanced the understanding of catalytic reactions. This commentary introduced the structure of SVUV-PIMS and then revisited an excellent work in science that utilized SVUV-PIMS to elucidate the mechanisms of dimethyl oxalate (DMO) hydrogenation into ethylene glycol over copper nanoparticles (Cu NPs) supported on dealuminated Beta zeolite (Beta-deAl). The observation of key intermediates, particularly (CHO)Cu₁^* species, using SVUV-PIMS provided real-time, in-situ insights into the dynamic behavior of Cu NPs in DMO hydrogenation. The findings highlighted the formation of a silanol nest and the presence of metallic Cu and Cu₂O phases following methanol treatment. This treatment helped maintain a small nanoparticle size, resulting in high EG yields and prolonged catalyst stability. Additionally, their catalyst addressed common issues, such as silica leaching, which often compromises the durability of CuSiO₂-based catalysts. By re-examining their work, this commentary underscores the transformative potential of SVUV-PIMS in catalysis research, and the operando adaptation of intermediates in reactions is invaluable for developing more efficient and durable catalysts.