Search

This study explores the synthesis, structural characterization, and host‐guest interactions of heteroatom bridged nanobelts, focusing on a cyclothianthrene nanobelt and a fused nanobelt incorporating thianthrene and phenoxathiin. Utilizing a cyclization‐followed‐by‐bridging synthetic approach, both molecular belts were successfully synthesized, and their structures confirmed through NMR and MALDI‐TOF‐MS analysis. Crystallographic studies revealed that the cyclothianthrene nanobelt adopts an octagonal column‐like conformation, while the hybrid belt forms an oval tub‐shaped shape, both exhibiting distinct assembly motifs. The host‐guest chemistry of these nanobelts was investigated with fullerenes (C60, C70, and PC61BM). The cyclothianthrene belt showed no interaction with these fullerenes, whereas the other belt demonstrated adaptive binding capabilities, forming stable complexes with C60 and C70 through π–π interactions and C−H⋅⋅⋅S hydrogen bonds. The binding constants indicated that the hybrid belt has a stronger affinity for C70 due to better size complementarity. Additionally, its interaction with PC61BM showcased a specific 1 : 1 binding mode despite exhibiting a smaller binding constant. This study underscores the impact of heteroatom incorporation on the structural and functional properties of nanobelts, offering insights for future molecular design strategies. [ABSTRACT FROM AUTHOR]

In recent years, blockchain technology has attracted substantial interest for its capability to transform supply chain management and finance. This paper employs evolutionary game theory to investigate the application of blockchain in mitigating financial risks within supply chains, taking into account the technology's maturity and the risk preferences of financial institutions. By modeling interactions among financial institutions, small and medium enterprises (SMEs), and core enterprises within the accounts receivable financing framework, this study evaluates blockchain's impact on their decision-making and its efficacy in risk reduction. Our findings suggest the transformative potential of blockchain in mitigating financial risks, solving information asymmetry, and enhancing collaboration between financial entities and SMEs. Additionally, we integrate smart contracts into supply chain finance, proposing pragmatic procedures for their deployment in real-world contexts. Via a detailed examination of blockchain's maturity and financial institutions' risk preferences, this research demonstrates the primary determinants of strategic decisions in supply chain finance and underscores how blockchain technology fosters system stability using risk mitigation. Our innovative contribution lies in the design of smart contracts for the ARF process, rooted in blockchain's core attributes of security, transparency, and immutability, thereby ensuring efficient operation and cost reduction in supply chain finance. [ABSTRACT FROM AUTHOR]

Two of the Shanghai metro lines suffered from severe side wear on the high rail, not only in sharp curves but also in large curves, and the service life of some rails on sharp curves was reduced by approximately 50% compared with the last rail replacement. Features and evolution rules for the rail side wear and the wheel flange wear were determined by field measurements and long-term monitoring. A rail wear prediction model, verified in our previous work, is used to reveal the influence of factors on rail wear. The results indicate that the poor lubrication condition at the rail gauge face is the main cause of severe side wear of the high rail, and the use of wheel profiles with low conicity and the loss of profile curvature of low rail profiles caused by the untimely maintenance also increase the side wear of the high rail. The service life of the high rail could be greatly extended by some countermeasures, such as repairing the worn shape of the low rail and repairing/improving the wayside lubrication system. [ABSTRACT FROM AUTHOR]

In recent years, the outbreaks of viral diseases have urgently demanded effective virus disinfection techniques. Among them, the use of cold atmospheric‐pressure plasma (CAP) is one of the most promising approaches. CAP generates electric fields, charged particles, reactive oxygen and nitrogen species, and ultraviolet. CAP can effectively inactivate various viruses in a short period, whether they are on surfaces, in water, or in aerosols, without significantly raising the substrate temperature. This review highlights that the simultaneous action of physical and chemical means is the key mechanism of CAP in virus inactivation. It systematically summarizes the characteristics of plasma devices suitable for different application scenarios and further points out the opportunities and challenges faced by plasma virus inactivation technology. [ABSTRACT FROM AUTHOR]

Due to the widespread use of lithium-ion batteries, evaluations of the flammability and explosive characteristics of carbon dust materials as anodes require attention. Carbon dust often reaches the micron/nano scale, and dust particle state and explosion risk generated in different industrial scenarios are different, which is in urgent need of research. Nanoscale dust has relatively static coagulation properties and shows characteristics of dispersion and reagglomeration under a certain airflow. The particle size characteristics affect its thermodynamic characteristics and various consequence parameters of dust explosion. The oxidation and combustion characteristics are mainly affected by dust particle size distribution characteristics. The apparent activation energy is mainly affected by the proportion of small and medium-sized particles and pre-exponential index factor is mainly affected by the dust overall average particle size and specific surface area. The explosion consequence parameters are affected by the thermodynamic parameters, by the disturbance state, particle distribution degree of dust cloud and other factors, which affect the heat radiation and heat transfer process to some extent resulting in different explosion consequence parameters. Due to the agglomeration characteristics of nano-level dust, the minimum ignition energy and minimum ignition temperature of nano-level dust are generally smaller than that of micron level dust. [ABSTRACT FROM AUTHOR]

Urban rail transit usually contains many small radius curved tracks, and wheel flange wear is prominent, which greatly reduces the service life and increases the maintenance and replacement costs of wheelsets. Two metro lines in Shanghai of China had suffered from severe flange wear since 2017, and the flange wear rate increased gradually over the next three years. This paper presents the understanding and treatment of severe flange wear through field measurement and numerical simulation. The investigation results indicated that the key factors causing severe flange wear were poor rail gauge face lubrication, the use of a low conicity wheel profile for trains running on the two metro lines containing many small radius curved tracks, and the lack of timely maintenance of low rail profiles. Three countermeasures were proposed to mitigate wheel flange wear, which were evaluated through wheel–rail matching analysis and wheel wear prediction. Then, two countermeasures, i.e. improving rail gauge face lubrication and employing the LM-30 wheel profile, were verified through field tests. [ABSTRACT FROM AUTHOR]

To overcome the thermodynamic and kinetic impediments of the Sabatier CO2 methanation reaction, the process must be operated under very high temperature and pressure conditions, to obtain an industrially viable conversion, rate, and selectivity. Herein, we report that these technologically relevant performance metrics have been achieved under much milder conditions using solar rather than thermal energy, where the methanation reaction is enabled by a novel nickel‐boron nitride catalyst. In this regard, an in situ generated HOB⋅⋅⋅B surface frustrated Lewis's pair is considered responsible for the high Sabatier conversion 87.68 %, reaction rate 2.03 mol gNi−1h−1, and near 100 % selectivity, realized under ambient pressure conditions. This discovery bodes well for an opto‐chemical engineering strategy aimed at the development and implementation of a sustainable 'Solar Sabatier' methanation process. [ABSTRACT FROM AUTHOR]