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The natural sunlight‐driven conversion of CO2 into valuable C2+ products is urgently being pursued at ambient pressure, yet it poses a substantial challenge. Herein, a bifunctional Cu‐promoted CoFe alloy catalyst is designed for the natural light‐driven CO2 hydrogenation into light olefins. Under a weak solar‐irradiation intensity of 0.45 kW m−2 (0.45 sun), the optimal catalyst exhibits excellent activity and selectivity, with an impressive 73.7% selectivity for C2+ hydrocarbons and an outstanding 56.5% selectivity for C2‐4 olefins, which is the best catalyst for C2+ hydrocarbons photosynthesis from natural sunlight to date. The bifunctional design of the catalyst combines the advantages of both metallic Cu and CoFe alloy components, providing a synergistic effect that enhances the CO2 hydrogenation performance. The Cu promoter plays a crucial role in enhancing the adsorption of CO2 and hydrogen spillover, while the CoFe alloy provides a stable coupling site of the C1 intermediate for promoting the C2‐4 olefins. This study provides new insights into the design of bifunctional catalysts for CO2 hydrogenation and opens up new possibilities for sustainable production of light olefins from renewable resources. [ABSTRACT FROM AUTHOR]

Malignant traffic accidents are typical devastating events suffered by the urban road network. They cause severe functional loss when loading on the urban road network is high, exerting a significant impact on the operation of the city. The resilience of a road network refers to its ability to maintain a certain level of capacity and service when disturbed by external factors and to recover after a disturbance event, which is a crucial factor in the construction of transportation infrastructure systems. A comprehensive understanding of the adverse effects of malignant traffic accidents on the urban road network is imperative, and resilience is a concept employed to systematically explain this. This study investigates the impact of malignant traffic accidents on the resilience of the urban road network. A simulation is carried out focusing on an ideal urban road network, describing the temporal and spatial distribution of the average speed of road sections in the network. Inspired by the simulation experiment results, the ideal resilience curve is summarized, and the theory of resilience concept portrayal is innovatively developed into “6R” (redundancy, reduction, robustness, recovery, reinforcement, and rapidity). Combining the topological and “6R” resilience attributes of the urban road network, the urban road network resilience evaluation system is constructed, which yields an all-round and full-process evaluation for the urban road network with malignant traffic accidents. Results show that under malignant traffic accidents, the resilience of high-class surface roads, such as primary roads, is the poorest, suggesting that more attention and resources must be devoted to high-class surface roads. This study on the urban road network deepens the understanding and portrayal of its resilience and proposes an evaluation method to analyze its performance under disruption events., Author(s): Yiding Lu [1]; Zhan Zhang (corresponding author) [2]; Xinyi Fang [1]; Linjie Gao [1]; Linjun Lu [1] 1. Introduction The continuous development of the urban road network has significantly [...]

This paper proposes a research framework for investigating the travel patterns of dockless bike-sharing and accomplishing the large-scale bike rebalancing at the city level. A case study involving Shanghai combines GPS-based bike-sharing usage data and road network data. First, the spatiotemporal mobility patterns are analyzed visually; then community detection is used to divide the study area into management sub-areas according to the mobility characteristics of bike-sharing users; in addition, a clustering algorithm is used to identify virtual stations. On this basis, a heuristic algorithm is used to generate a rebalancing scheme that enables multiple visits to a given station. The results show that Shanghai can be divided into 28 bike-sharing management sub-areas. Static rebalancing based on the identified management sub-areas reduces the number and driving distance of rebalancing vehicles in use, which is a better outcome than that with a method based on administrative divisions. [ABSTRACT FROM AUTHOR]

Predicting the intention of mode choice is indispensable for policymakers to develop sustainable transportation in large cities. This paper constructs a conceptual framework and tests it in the travel mode sector to investigate the influence mechanism between commuter's low-carbon literacy and intention of mode choice. Commuter's low-carbon literacy (LCL) was assessed through four critical attributes: low-carbon knowledge (LCK), low-carbon awareness (LCAW), low-carbon habits (LCH) and low-carbon affection (LCAF). Based on a questionnaire survey in Shanghai, empirical evidence was concluded using the Structural Equation Model of Partial Least Square (PLS-SEM). The results of this study are as follows: (1) low-carbon knowledge, habits and affection have direct influences on commuter's intention of mode choice, whereas low-carbon awareness influences commuter's intention through these three low-carbon attributes indirectly; (2) low-carbon affection has the highest impact rating on the intention of mode choice in both performance and importance; (3) commuting trips are less closely associated with the influence of low-carbon literacy than other trips. These findings have several implications for transportation demand management and are beneficial for urban trip structure optimization. [ABSTRACT FROM AUTHOR]

Sunlight driven formic acid decomposition has great potential to supply high-purity H2 without consuming fossil fuel-derived energy. However, a trace amount of CO invariably exists in the obtained H2 and the H2 production rate is always lower than 278 mmol g−1 h−1. Here, we found that high quality MoS2 grown on graphene decorated on Ni foam (Ni/G/MoS2) was active and stable for H2 production from thermocatalytic formic acid decomposition without CO presentation and first principles calculation confirmed that the perfect surface terminating sulfur of MoS2 changed the reaction path of intermediates, thus inhibiting the production of CO. Furthermore, a reaction device constructed with Cu2Se can heat catalysts to 120 and 260 °C under 0.25 kW m−2 and 1 kW m−2 (1 Sun) of irradiation, respectively. By using the system of the Cu2Se based reaction device and Ni/G/MoS2, a CO free H2 production rate of 982 mmol g−1 h−1 was achieved under 0.6 Sun of irradiation, 3.5 times higher than the previous record of photocatalytic formic acid decomposition. Therefore, this work provides a new viewpoint for large scale CO free H2 production in a sustainable and green way. [ABSTRACT FROM AUTHOR]

When performing microscopic traffic simulations, a premise is to have appropriately calibrated parameter values. This is often computationally expensive as it requires repeatedly running simulations. In this paper, we propose a machine learning (ML) + particle swarm optimization (PSO)-based methodology for calibrating microscopic traffic simulator parameters to improve computational efficiency. We first develop ML models that input the parameters to predict simulation outputs. Four machine learning models: decision tree, support vector machine, Gaussian process regression, and artificial neural networks are considered. The best-performing model is then embedded in PSO to seek the set of parameters that minimizes the difference between the predicted simulation outputs and the field observations. The ML+PSO methodology is applied to TransModeler using field data in Shanghai, China. We find that artificial neural networks yield the best prediction accuracy. Furthermore, PSO with embedded artificial neural networks shows superior computational efficiency and effectiveness.. [ABSTRACT FROM AUTHOR]

The CsPbBr3 quantum dots (QDs) modified vertically layered MoS2/Si (V‐MoS2/Si) heterojunction is successfully prepared. It is found that the resulting photodetector realizes the UV–vis–NIR broad‐spectrum detection with good sensitivity and fast photoresponse speed. Typically, the responsivity and response/recovery time towards 808 nm reach up to 0.975 A W−1 and 6.8/6.7 ms, respectively. Furthermore, it is demonstrated that with the modification of CsPbBr3 QDs, the responsivities of the pure V‐MoS2/Si‐based photodetector for 532, 671, and 808 nm detection are boosted by 5.43, 2, and 5.45 times, respectively. The enhanced sensing performance is attributed to the vis–NIR light harvesting capability and excellent electrical transporting property of the CsPbBr3 QDs. Most importantly, the flexibility can be applied to the wearable devices for various working environments. The present work pushes the development of the flexible devices for broadband spectrum detection faced to practical application. [ABSTRACT FROM AUTHOR]