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The collaborative optimization of speed and energy management for fuel cell hybrid electric vehicles (FCHEVs) in car-following scenario is an important and effective means to achieve vehicle energy conservation. In view of the unclear coupling relationship between dual energy source degradation and energy consumption in existing strategies, and the difficulty of considering both global optimization and real-time performance, this paper proposes a Stackelberg game based FCHEV following energy management strategy. Firstly, models for energy consumption and performance degradation of fuel cells/lithium batteries are established and incorporated into a unified dimensional comprehensive vehicle cost function. Secondly, a hierarchical decoupling based energy management strategy for vehicle following is proposed to achieve decoupling control of vehicle following speed and power distribution. Thirdly, considering safety, comfort, fuel economy, and energy durability, a bi-level programming model corresponding to the car-following control layer and energy management layer is established. Based on the Stackelberg game theory, a bi-level differential genetic algorithm is designed to offline optimize the core parameters of the strategy. Finally, simulation and experimental results show that compared to the model predictive control method, this method can reduce average vehicle spacing error by 37.7%, average impact by 2.4%, equivalent hydrogen consumption by 9.3%, and energy degradation cost by 13.9%, achieving a balance between optimized performance and real-time performance. [ABSTRACT FROM AUTHOR]

Doping–dedoping chemistry lays the cornerstone for converting heteroatom dopants into intrinsic defects as the emerging active sites of carbon catalysts, but the defect content is yet hindered by inadequate doping efficiencies. Comprehending crucial factors behind the doping of pristine carbon and their correlation to the catalytic properties of dedoped carbon is thus of high significance. Here, the overlooked impact of native defects in pristine carbon on dopant‐mediated defect engineering of carbon catalysts is explicitly unveiled. Intact fullerene (C60), C60‐derived carbon, and carbon black in distinct pentagon/edge defect states are employed as respective precursors to undergo a nitrogen doping–dedoping treatment. Theoretical and experimental evidence consistently indicates that native pentagons change the preferred N doping site from the edge to the basal plane, leading to a substantially higher doping level. Importantly, in addition to pentagons from the removal of zigzag‐edged pyridinic N, N dopants in in‐plane pentagons are more easily dedoped than those in hexagons, generating even more pentagons in a new pentagon–heptagon–pentagon structure as oxygen reduction active sites. The optimized defect‐rich carbon gives an outstanding half‐wave potential of 0.834 V (0.846 V for Pt/C) via the four‐electron pathway, excellent long‐term durability, and prospective applicability in zinc–air batteries. [ABSTRACT FROM AUTHOR]

A functionalized ethylene–vinyl-alcohol (EVOH) nanofibrous membrane (NFM) was fabricated via co-electrospinning H4SiW12O40 (SiW12) and EVOH first, and then grafting citric acid (CCA) on the electrospun SiW12@EVOH NFM. Characterization with FT-IR, EDX, and XPS confirmed that CCA was introduced to the surface of SiW12@EVOH NFM and the Keggin structure of SiW12 was maintained well in the composite fibers. Due to a number of carboxyl groups introduced by CCA, the as-prepared SiW12@EVOH-CCA NFM can form a high number of hydrogen bonds with CR, and thus can be used to selectively absorb congo red (CR) in aqueous solutions. More importantly, the CR enriched in the NFM can be rapidly degraded via photocatalysis. SiW12 in the NFM acted as a photocatalyst, and the hydroxyl groups in the NFM acted as an electron donor to accelerate the photodegradation rate of CR. Meanwhile, the SiW12@EVOH-CCA NFM was regenerated and then exhibited a relatively stable adsorption capacity in five cycles of filtration–regeneration. The bifunctional nanofibrous membrane filter showed potential for use in the thorough purification of dye wastewater. [ABSTRACT FROM AUTHOR]

With the development of medical diagnosis and treatment, knowing the mechanical properties of living tissues becomes critical. The aim of this study was to investigation material properties of the fresh porcine kidney and the parametric characterization of its viscoelastic material behavior. The material investigation included uniaxial tension tests in different strain rates, relaxation tests, as well as hydrostatic compression tests on the samples extracted from the fresh porcine kidney cortex. Tension tests and relaxation tests were performed by a planar dog-bone specimen with a micron loading testing machine. Hydrostatic compression tests were performed on the kidney cylinder sample which was placed in a compression chamber. Furthermore, a nonlinear viscoelastic model recently proposed by us was employed to characterize the tension data at different strain rates and relaxation test data. The the experimental and numerical results show that the stress-strain relations of the porcine kidney cortex at different strain rates in tension are presented for the first time and a higher strain rate results in higher ultimate strength and initial Young modulus but a lower rupture strain. A damage-dependent visco-elastic model is employed to model the tension data at different strain rates and relaxation data and exhibits a good agreement with the experimental data, which also demonstrates that the damage has an obvious influence on the stress-strain relation. Through comparison with the existing reference covering the uniaxial compression data, it seems that the mechanical behavior of the porcine kidney cortex manifests a stress state-dependent mechanical behavior. The ultimate strength and rupture strain are larger in compression than that in tension. [ABSTRACT FROM AUTHOR]

Hair follicle (HF) regeneration during wound healing continues to present a significant clinical challenge. Dermal papilla cell-derived exosomes (DPC-Exos) hold immense potential for inducing HF neogenesis. However, the accurate role and underlying mechanisms of DPC-Exos in HF regeneration in wound healing remain to be fully explained. This study, represents the first analysis into the effects of DPC-Exos on fibroblasts during wound healing. Our findings demonstrated that DPC-Exos could stimulate the proliferation and migration of fibroblasts, more importantly, enhance the hair-inducing capacity of fibroblasts. Fibroblasts treated with DPC-Exos were capable of inducing HF neogenesis in nude mice when combined with neonatal mice epidermal cells. In addition, DPC-Exos accelerated wound re-epithelialization and promoted HF regeneration during the healing process. Treatment with DPC-Exos led to increased expression levels of the Wnt pathway transcription factors β-catenin and Lef1 in both fibroblasts and the dermis of skin wounds. Specifically, the application of a Wnt pathway inhibitor reduced the effects of DPC-Exos on fibroblasts and wound healing. Accordingly, these results offer evidence that DPC-Exos promote HF regeneration during wound healing by enhancing the hair-inducing capacity of fibroblasts and activating the Wnt/β-catenin signaling pathway. This suggests that DPC-Exos may represent a promising therapeutic strategy for achieving regenerative wound healing. [ABSTRACT FROM AUTHOR]

The UN's Sustainable Development Goals (SDGs) highlight the role of debt sustainability in achieving sustainable development. China's Belt and Road Initiative (BRI) is an international cooperation effort that is endorsed by over 150 countries and organizations. Given the alignment between BRI development goals and the SDGs, the issue of debt sustainability in BRI countries warrants attention. While existing studies focus on sovereign risk in debt sustainability, there is a lack of emphasis on currency risk, indicating a need for further investigation to mitigate risks and comprehensively evaluate debt stability. Using data from 142 countries, this study examines currency risk reduction in BRI countries by assessing currency competitiveness. We find that the US dollar (USD) is the most competitive currency among BRI countries, followed by the Euro (EUR), Chinese yuan (CNY), sterling pound (GBP), and Japanese yen (JPY). The USD maintains its competitive edge over time, making it the preferred choice, with the EUR as a less optimal option and the CNY showing potential. Geographically, the EUR's close ties with BRI countries lend it prominence, followed by the USD, with the CNY gaining traction. GBP and JPY are considered conservative choices. Recommendations for currency selection vary based on countries' competitiveness, bilateral relationships, and development status. [ABSTRACT FROM AUTHOR]

This study introduces a new wide-bandgap graphene-like structure, denoted as C6BN, achieved by incorporating an eight-electron BN pair, substantially modifying its electronic properties. Utilizing extensive density functional calculations, we comprehensively analyzed the stability, electronic structure, mechanical properties, and optical-electrical characteristics of C6BN. Our investigations reveal the material's exceptional thermodynamic, mechanical, and dynamic stability. Notably, the calculated wide bandgap of 2.81 eV in C6BN, supported by analyses of energy levels, band structures, and density of states, positions it as a promising two-dimensional wide-bandgap semiconductor. Additionally, C6BN exhibits isotropic mechanical features, highlighting its inherent flexibility. Remarkably, our calculations indicate an ultra-low dielectric constant (k = 1.67) for C6BN, surpassing that of well-established third-generation semiconductors. Further exploration into the thermoelectric properties of C6BN demonstrates its promising performance, as evidenced by calculations of thermal conductivity (κ), power factor (P), and Seebeck coefficient (S). In summary, our findings underscore the significant potential of the proposed C6BN structure as a flexible two-dimensional material poised to drive future advancements in electronic and energy-related technologies. [ABSTRACT FROM AUTHOR]