Recyclable V2O5/g-C3N4 Heterojunction-Catalyzed Visible-Light-Promoted C3-H Trifluoromethylation of Quinoxalin-2-(1H)-ones.

A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.

Paired Electrolysis-Enabled Arylation of Quinoxalin-2(1H)-ones.

The first paired electrolysis-enabled arylation of quinoxalin-2(1H)-ones was achieved using cyanoarenes as the arylation reagents. A variety of 3-arylquinoxalin-2(1H)-ones with various important functional groups were obtained in moderate to good yields under metal- and chemical oxidant-free conditions. With a pair of reductive and oxidative processes occurring among the substrates and reaction intermediates, the power consumption can be dramatically reduced.

Deformation characteristics and mechanism of Mala paleo-landslide during the Miaowei reservoir initial impoundment period.

This study employs a multifaceted approach, encompassing field investigations, borehole surveys, surface deformation displacement monitoring, deep-seated deformation monitoring, and numerical simulation analysis, to conduct an exhaustive examination of the deformation processes and characteristics exhibited by the Mala Landslide. The findings elucidate a close correlation between the deformation of the Mala Landslide and the elevation of the reservoir water level. During the escalation of the reservoir water level, the landslide body progressively developed surface cracks, spanning from the frontal edge to the rear edge. The centre of the sliding body is situated in the central-lower downstream region, and presently, the landslide is undergoing a phase of comprehensive creep deformation. Due to the reservoir water level fluctuation rate being greater than the permeability coefficient, the deformation of the landslide displays a delayed response. As the reservoir water level reaches 1401 m during high-water operation, the two important ingredients, the buoyancy weight reduction effect and the influence of submerged reservoir water, significantly reduce the sliding resistance of the sliding mass, thereby exacerbating the deformation of the landslide. Following a comprehensive analysis of the findings, it can be firmly concluded that this landslide conforms to the characteristic traits of a typical buoyant force reduction type-retrogressive type landslide.

MCD-Net: Toward RGB-D Video Inpainting in Real-World Scenes.

Video inpainting gains an increasing amount of attention ascribed to its wide applications in intelligent video editing. However, despite tremendous progress made in RGB video inpainting, the existing RGB-D video inpainting models are still incompetent to inpaint real-world RGB-D videos, as they simply fuse color and depth via explicit feature concatenation, neglecting the natural modality gap. Moreover, current RGB-D video inpainting datasets are synthesized with homogeneous and delusive RGB-D data, which is far from real-world application and cannot provide comprehensive evaluation. To alleviate these problems and achieve real-world RGB-D video inpainting, on one hand, we propose a Mutually-guided Color and Depth Inpainting Network (MCD-Net), where color and depth are reciprocally leveraged to inpaint each other implicitly, mitigating the modality gap and fully exploiting cross-modal association for inpainting. On the other hand, we build a Video Inpainting with Depth (VID) dataset to supply diverse and authentic RGB-D video data with various object annotation masks to enable comprehensive evaluation for RGB-D video inpainting under real-world scenes. Experimental results on the DynaFill benchmark and our collected VID dataset demonstrate our MCD-Net not only yields the state-of-the-art quantitative performance but successfully achieves high-quality RGB-D video inpainting under real-world scenes. All resources are available at https://github.com/JCATCV/MCD-Net.

Ferrocene/air double-mediated FeTiO3-photocatalyzed semi-heterogeneous annulation of quinoxalin-2(1H)-ones in EtOH/H2O.

With both ferrocene and air as the redox catalysts, for the first time, the low-cost natural ilmenite (FeTiO3) was successfully used for photocatalytic bond formations. Under the assistance of a traceless H-bond, and HCHO as the methylene reagent, a variety of imidazo[1,5-a]quinoxalinones were semi-heterogeneously photosynthesized in high yields with good functional group compatibility.

Time-domain immersed-boundary simulation of acoustic propagation between two spherical gas bubblesa).

Acoustic fields and resonance responses from two spherical gas bubbles are investigated using a time-domain simulation. Interior acoustic fields are obtained simultaneously from the simulation of the entire acoustic field propagation with an immersed-boundary method. The linear resonance responses are obtained and discussed for each of the bubbles with respect to the respective interior gas velocities. Also, these are analyzed in the frequency domain in terms of the coupled interactions. Unlike previous numerical and analytical solutions, the method allows for two bubbles of different sizes and shapes to be in contact with each other, which is representative of applicable underwater scattering targets.

Time-domain simulation of acoustic wave scattering and internal propagation from a gas bubble of various shapes.

Acoustic scattering and resonances of gas bubbles are computed using a time-domain simulation based on numerical solutions of the conservation laws. The time histories of scattered pressure and fluid velocity, outside and inside the bubble, are obtained simultaneously from an immersed-boundary method allowing for the investigation of exterior and interior fields for non-spherical geometries. The acoustic resonances of the bubble are investigated for various bubble sizes, shapes, and inner gas parameters and compared in limiting cases to the partial wave scattering solutions for spherical bubbles. The dynamics of the gas motion and its associated contribution to resonance response has received little attention in previous analytical and numerical formulations. In this study, the acoustic propagation and motion inside the interior gas is investigated with respect to the monopole resonance with the combined time-domain simulation and immersed-boundary method. For the non-spherical prolate and oblate shapes, the scattering and resonance behaviors are compared with the approximate analytical results based on the shape factor method. The simulation method can be extended to less-understood shapes relevant to underwater and physical acoustics, such as "pancake-shaped" or "cigar-shaped" bubbles, as well as to spatial and time-dependent forcing.