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We report the one-pot synthesis of N-CF3heteroaryl amides (NTFMHA) from heteroaryl carboxylic acids and sterically hindered isothiocyanates, including various amino acid analogues, in the presence of AgF. The key to this reaction is the utilization of free heteroaryl acyl chlorides, rather than their corresponding hydrochloride salts. This method represents a complementary method of our previous work and enables modification to a variety of previously inaccessible structures, including α-tertiary amines and N-CF3-modified pharmaceuticals.

To overcome the strength-toughness inversion relationship in steel/Fe matrix composites, a novel W-WC/Fe composite fiber-reinforced Fe matrix composite ((W-WC/Fe)f-IMC) with exceptional strength and toughness was fabricated by an in-situ fabrication method combining infiltration and in-situ solid-phase diffusion. The (W-WC/Fe)f-IMC consists of aligned W-WC/Fe composite fibers embedded in an Fe matrix. The W-WC/Fe composite fiber exhibits a characteristic core-shell structure on its cross section, with a resilient metal W fiber serving as the core and a robust annular WC-Fe layer acting as the shell. Due to the inward-outward growth and the gradient microstructure of the WC-Fe layer, the interface bonding strength between the W fiber/WC-Fe layer and the WC-Fe layer/matrix remains excellent. As a result, the (W-WC/Fe)f-IMC achieves an exceptional fracture strain of 35.5 ± 1.3 %, while maintaining high yield strength of 701 ± 16 MPa and ultimate compression strength of 1100 ± 18 MPa, surpassing those of cast Fe, which had values of 26.9 ± 1.1 %, 365 ± 20 MPa, and 834 ± 15 MPa, respectively. The simultaneous enhancement of the strength and toughness in (W-WC/Fe)f-IMC can be primarily attributed to the synergistic coupling effect between the high strength W-WC/Fe composite fibers and the tough matrix. The strategy proposed in this study holds promise as a method to alleviate the trade-off between strength and ductility in steel/Fe matrix composites.

• Ferromagnetic TiO 2 was prepared by regulation of crystal structure and defects. • The saturation magnetisation (M S) was measured to be as high as 0.0014 emu/g. • Experiments and simulation are used to investigate the ferromagnetism mechanism. • The photoelectrochemical performance was improved by ferromagnetic field in the bulk. • The proposed approach can be used to other oxide systems. The use of the internal magnetic field of ferromagnets can effectively promote charge separation and transfer (CST) in photoelectrochemical energy conversion. However, photoelectrochemical materials with a ferromagnetic field are scarce, and the internal magnetic field is negligible in nonferromagnetic materials. To address this issue, we propose a rational method for preparing ferromagnetic TiO 2 powder using controllable oxygen vacancies in anatase TiO 2 with co-exposed {001} and {101} facets. Accordingly, an excellent saturation magnetisation of 0.0014 emu/g in TiO 2 is achieved owing to an asymmetric and uneven charge distribution. Compared with that of nonferromagnetic TiO 2 , the efficiency of photocatalytic hydrogen generation of ferromagnetic TiO 2 is improved by 0.64 times. The enhancement of photocatalytic hydrogen generation is due to the different forces exerted on the electrons and holes in the magnetic field, which significantly improve the photogenerated CST efficiency of ferromagnetic TiO 2. This result highlights the significant role of the synergistic regulation of the crystal structure and defects in regulating the ferromagnetic characteristics of materials. The findings of this study provide guidance for leveraging point defects to promote CST for high-efficiency solar-energy conversion systems. Ferromagnetic TiO 2 with co-exposed {001} and {101} facets was prepared via controllable oxygen vacancies. The different forces exerted on the electrons and holes in the magnetic field significantly improve the photogenerated CST efficiency of ferromagnetic TiO 2 [Display omitted] [ABSTRACT FROM AUTHOR]

Both high-level and high-resolution feature representations are of great importance in various visual understanding tasks. To acquire high-resolution feature maps with high-level semantic information, one common strategy is to adopt dilated convolutions in the backbone networks to extract high-resolution feature maps, such as the dilatedFCN-based methods for semantic segmentation. However, due to many convolution operations are conducted on the high-resolution feature maps, such methods have large computational complexity and memory consumption. To balance the performance and efficiency, there also exist encoder-decoder structures that gradually recover the spatial information by combining multi-level feature maps from a feature encoder, such as the FPN architecture for object detection and the U-Net for semantic segmentation. Although being more efficient, the performances of existing encoder-decoder methods for semantic segmentation are far from comparable with the dilatedFCN-based methods. In this paper, we propose one novel holistically-guided decoder which is introduced to obtain the high-resolution semantic-rich feature maps via the multi-scale features from the encoder. The decoding is achieved via novel holistic codeword generation and codeword assembly operations, which take advantages of both the high-level and low-level features from the encoder features. With the proposed holistically-guided decoder, we implement the EfficientFCN architecture for semantic segmentation and HGD-FPN for object detection and instance segmentation. The EfficientFCN achieves comparable or even better performance than state-of-the-art methods with only 1/3 of their computational costs for semantic segmentation on PASCAL Context, PASCAL VOC, ADE20K datasets. Meanwhile, the proposed HGD-FPN achieves $>2\%$>2% higher mean Average Precision (mAP) when integrated into several object detection frameworks with ResNet-50 encoding backbones.