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Grasping and manipulating various kinds of objects cooperatively is the core skill of a dual-arm robot when deployed as an autonomous agent in a human-centered environment. This requires fully exploiting the robot's versatility and dexterity. In this work, we propose a general framework for dual-arm manipulators that contains two correlative modules. The learning-based dexterity-reachability-aware perception module deals with vision-based bimanual grasping. It employs an end-to-end evaluation network and probabilistic modeling of the robot's reachability to deliver feasible and dexterity-optimum grasp pairs for unseen objects. The optimization-based versatility-oriented control module addresses the online cooperative manipulation control by using a hierarchical quadratic programming formulation. Self-collision avoidance and dual-arm manipulability ellipsoid tracking with high reliability and fidelity are simultaneously achieved based on a learned lightweight distance proxy function and a speed-level tracking technique on Riemannian manifold. Intrinsic system safety is guaranteed, and a novel interface for skill transfer is enabled. A long-horizon rearrangement experiment, a bimanual turnover manipulation, and multiple comparative performance evaluation verify the effectiveness of the proposed framework.

Light-driven direct conversion of methane to formic acid is a promising approach to convert methane to value-added chemicals and promote sustainability. However, this process remains challenging due to the complex requirements for multiple protons and electrons. Herein, we report the design of WO3-based photocatalysts modified with Pt active sites to address this challenge. We demonstrate that modulating the dimensional effect of Pt on the WO3support is key to enhancing the catalytic performance of selective CH4-to-HCOOH conversion. The Pt nanoparticles on WO3exhibit superior conversion rate, selectivity and durability in the production of HCOOH compared to the Pt-free sample and WO3decorated with Pt single atoms. The optimal PtNPs-WO3catalyst achieves a HCOOH conversion rate of 17.7 mmol g–1, with 84% selectivity and stability maintained for up to 48 h. Mechanistic studies show that the protonation of O2to hydroxyl radicals is the limiting step for HCOOH yield. Pt nanoparticles can facilitate electron transfer and promote O2dissociation, generating hydroxyl radicals via a proton-coupled electron transfer process. This process provides sufficient protons to lower the formation barrier for •OH radicals, thereby promoting the activation of CH4. In addition, Pt nanoparticles regulate the adsorption of oxygenated hydrocarbon intermediates, increasing the selectivity of the reaction. This work advances our understanding of catalyst design for methane conversion and the effective regulation of complex reaction pathways.

Photocatalytic CO2cycloaddition is a promising approach for CO2value-added processes. However, the efficiency of plasmon-assisted CO2cycloaddition still needs to be improved and the reaction mechanism is unclear. Herein, g-C3N4/Ag (ACN–Ag) hybrids exhibited superior activity of CO2cycloaddition by coupling a semiconductor into the plasmonic system, in which the ACN grafting amino group by the formation of carbon vacancies can enhance CO2chemisorption; meanwhile, photo-generated electrons from ACN transfer to Ag to form high-energy electrons, which can activate propylene oxide, accelerating the ring-opening step. Importantly, photo-generated electron injection from ACN to Ag and the interaction between Ag nanoparticles and ACN were confirmed by single-particle photoluminescence spectroscopy. The wavelength-dependent activity demonstrated that the plasmon excitation is crucial for the reaction. Moreover, in situ single-particle PL quenching caused by propylene oxide and in situ electron paramagnetic resonance verified the activation of propylene oxide by ACN–Ag. This work is conducive to an in-depth understanding of the mechanism of CO2cycloaddition at the single-particle level and provides guidance for the organic synthesis.

In this study, we have provided a facile solution to synthesize well-aligned titanium dioxide nanorods by using hydrothermal reaction. By calcining the materials under different atmospheres and temperatures, a batch of titanium dioxides with excellent oxygen evolution reaction(OER) catalytic efficiency were obtained. This new structured TiO2photoanode material yields a high photocurrent density of 5.69 mA/cm2at 1.23 V vs.reversible hydrogen electrode(RHE) under simulated solar light(100 mW/cm2). Surface photovoltage techniques and other measurements were carried out to confirm that the enhanced photoelectrochemical performances were attributed to the synergistic effect of the phase junction and a certain content of surface states, which accelerate the separation and transmission of the photogenerated charges. This material with phase junction and surface states promises a potential application in the field of photoelectric catalysis under solar light.

With the rapid development of light-rail public transportation, video-based obstacle detection is becoming an essential and foregoing task in driver assistance systems. The system should be able to automatically survey the tramway using an onboard camera. However, the functioning of the system is challenging due to the presence of various ground types, different weather and illumination conditions, as well as varying time of acquisition. This article presents a real-time tramway detection method that deals efficiently with various challenging situations in real-world urban rail traffic scenarios. It first uses an adaptive multilevel thresholding method to segment the regions of interest of the tramway, in which the threshold parameters are estimated using a local accumulated histogram. The approach then adopts the region growing method to decrease the influence of environmental noise and to predict the trend of the tramway. The experiment validation of this study proves that the method is able to correctly detect tramways even in challenging scenarios and uses lesser computational time to meet the real-time demand.

In this work, a Bi-based metal–organic framework (MOF; Bi-MMTAA) with 2-mercapto-4-methyl-5-thiazoleacetic acid (MMTAA) as the organic ligand is synthesized. The crystal structure of Bi-MMTAA was determined by single-crystal X-ray diffraction. Theoretical calculations reveal that Bi-MMTAA is a p-type semiconductor, and electrons can delocalize through the π-conjugation when excited by a photon with an energy higher than the Bi-MMTAA band gap, which is beneficial to charge separation and transfer. The photoelectrical properties suggest that free electrons can be produced over Bi-MMTAA under light irradiation. The photocatalytic results suggest that Bi-MMTAA can decolorize rhodamine B (RhB) and oxidize phenylboronic acid to phenol under visible light (λ > 420 nm), with superoxide radicals being the main reactive oxygen species. Our results enrich the family of Bi-based MOFs and may inspire further exploration of Bi-based MOFs, including both synthesis and potential applications.