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Aiming at the issue that the noise generated during image acquisition and transmission would degrade the ability of subsequent image processing, a generative adversarial network (GAN) based multi-channel image denoising algorithm was developed. The noisy color image could be separated into red-green-blue (RGB) three channels via the proposed approach, and then the denoising could be implemented in each channel on the basis of an end-to-end trainable GAN with the same architecture. The generator module of GAN was constructed based on the U-net derivative network and residual blocks such that the high-level feature information could be extracted effectively via referring to the low-level feature information to avoid the loss of the detail information. In the meantime, the discriminator module could be demonstrated on the basis of fully convolutional neural network such that the pixel-level classification could be achieved to improve the discrimination accuracy. Besides, in order to improve the denoising ability and retain the image detail as much as possible, the composite loss function could be depicted by the illustrated denoising network based on the following three loss measures, adversarial loss, visual perception loss, and mean square error (MSE). Finally, the resultant three-channel output information could be fused by exploiting the arithmetic mean method to obtain the final de-noised image. Compared with the state-of-the-art algorithms, experimental results show that the proposed algorithm can remove the image noise effectively and restore the original image details considerably. [ABSTRACT FROM AUTHOR]

The high-temperature oxidation of ZrAl2 upon exposure to pure O2 at 800–950 °C was studied in terms of the oxidation kinetics and the formation mechanism of the oxide layer. The alloy followed parabolic oxidation kinetics, and the activation energy of oxidation was 239 ± 14 kJ/mol. During the early stages of oxidation below 850 °C, a single-layer oxide formed due to the crystallization of the initially formed amorphous oxide layer. A multilayer oxide structure developed at higher temperatures, due to the slightly higher affinity of oxygen for Zr than for Al and the oxidation-induced compositional changes. [ABSTRACT FROM AUTHOR]

The crystal phase plays an important role in controlling the properties of a nanomaterial; however, it is a great challenge to obtain a nanomaterial with high purity of the metastable phase. For instance, the large‐scale synthesis of the metallic phase MoS2 (1T‐MoS2) is important for enhancing electrocatalytic reaction, but it can only be obtained under harsh conditions. Herein, a spatially confined template method is proposed to synthesize high phase‐purity MoS2 with a 1T content of 83 %. Moreover, both the confined space and the structure of template will affect the purity of 1T‐MoS2; in this case, this approach was extended to other similar spatially confined templates to obtain the high‐purity material. The obtained ultrathin nanosheets exhibit good electrocatalytic activity and excellent stability in the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Tuning the electrocatalytic selectivity and long‐term stability for industrially significant, yet reactively unfavorable products, remains a challenge in oxygen reduction. Herein, the Au/TiO2 catalysts with strong metal–support interactions (SMSI) are designed and synthesized through an in situ auto‐reduction of Au‐modified Ti‐MOF. Highly dispersed ultra‐low loading of Au NPs strongly capsulated in porous TiO2 substrate, together with conductive carbon derivated from MOFs, enables Au/TiO2 electrocatalysts to achieve excellent H2O2 electrosynthesis through the two‐electron oxygen reduction reaction (2e ORR). Au(1.0)/TiO2 (0.52 wt% Au loading) exhibited a high selectivity of 90%, a remarkable Faradaic efficiency of 98%, and 72.2 mg L−1 h−1 H2O2 production. Highly dispersed Au NPs promote active site exposure, while the conductive carbon and the porous superstructure enhance mass diffusion. Notably, the SMSI between Au NPs and TiO2 substrate leads to superb stability (over 168 h) of the electrocatalysts, as it ensures continuous electronic interactions. Experimental characterizations and density functional theory (DFT) simulations further revealed that the SMSI effect medicates the activation of the *OOH intermediate formation and the d‐band center, which are conductive to 2e ORR. Moreover, this strategy provides a potential way toward high‐performance electrocatalysts in flow system devices for continuously purifying sewage and chemical bleaching in extreme environments. [ABSTRACT FROM AUTHOR]

Nanowires are major building components for nanotechnology. The growth and the assembly of nanowires are often complicated and expensive, which has impeded practical applications of such nanotechnology. This work discloses a Vapor-Defect-Solid (VDS) mechanism for growth of nanowall networks (NanoNets), by exploring a spontaneous interaction of vapor and defect networks in polycrystalline materials. A kinetic model analysis of the precondition and the characteristics of the VDS growth process is presented. The VDS growth mechanism allows straightforward, fast growth of two-dimensional NanoNets at near room temperature from vapor sources with a very high production yield, and thus holds potential as a general route for large-area production of NanoNets at a reduced cost. The VDS growth mechanism further allows exploration of fundamental knowledge of grain-boundary networks in nanocrystalline materials, and opens new avenues for grain-boundary engineering. [ABSTRACT FROM AUTHOR]

Ti2AlNb‐based alloys are synthesized by spark plasma sintering from pre‐alloyed and ball‐milled Ti–22Al–25Nb powder, and the structure of the alloys is regulated by aging at 800 °C for 0.5, 1, 2, and 3 h. Comparison of phase composition, microstructure, and mechanical properties are made in this study. Aging in the B2 + O phase region refers to the reversible transformation of B2 ↔ O. Complete B2 + O Widmanstätten structure is obtained in the aged alloys synthesized from pre‐alloyed powder, and the ones from milled powder contain acicular O and B2 + O Widmanstätten structure. Ball milling eliminates the B2 + O colonies, facilitates the continuous transformation of O → B2, and induces acicular O in the alloys; however, the hardness of these alloys is decreased in contrast with that of the ones synthesized from pre‐alloyed powder. Owing to the precipitation strengthening based on a large amount of fine O‐phase precipitates, the 3 h aged alloy from pre‐alloyed powder exhibits comprehensive mechanical properties with Vickers hardness of 448 ± 9 HV, ultimate tensile strength of 730 MPa, and elongation of 0.43%. [ABSTRACT FROM AUTHOR]