The adjustment of the initial synthesis solution pH affects the structure and stability of C16 Co-MCM-41. This pH effect was systematically investigated using N 2 physisorption, TPR, in-situ FTIR, and X-ray absorption spectroscopy. Co-MCM-41 catalysts with the same pore size but greater porosity were synthesized with increasing pH from 10.5 to 12. The distribution of Co ions with respect to being on the pore wall or in the silica wall framework was changed by pH; higher pH produced Co ions mainly distributed just subsurface or in the interior of the silica wall. These pH effects significantly affected the reduction stability of the Co-MCM-41 sample similar to that of the pore radius of curvature effect (Lim et al., J. Phys. Chem. B, 109 (2005) 2285), resulting in stable and size controllable sub-nanometer Co clusters that are useful for catalyst design for specific reactions.

A new organic compound was exploited as a highly stable organic anode for potassium-ion batteries.

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High-quality single-walled carbon nanotubes (SWNT) with high yield were produced by using small-pore Co-MCM-41 catalyst, templated by a C10 surfactant and containing 3 wt % Co. A complete incorporation of Co ions in the silica matrix without formation of surface Co oxides and the contact time of the reaction, in the catalyst synthesis and the SWNT production, respectively, were the most critical factors to be considered. By controlling the reduction temperature and contact time in the reaction, the carbon yield could reach 34 wt % or higher with a selectivity of 96 wt % to SWNT. The metal content after purification of SWNT by base-acid treatments was 0.7 wt %, and the surface area was as high as 1800 m 2 /g. The metal surface occlusion effect by amorphous silica might play a key role in the stabilization of the completely reduced Co metallic clusters in the SWNT synthesis procedure, using small-pore C10 Co-MCM-41.

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In this paper, we present new data pre-processing and augmentation techniques for DNN-based raw image denoising. Compared with traditional RGB image denoising, performing this task on direct camera sensor readings presents new challenges such as how to effectively handle various Bayer patterns from different data sources, and subsequently how to perform valid data augmentation with raw images. To address the first problem, we propose a Bayer pattern unification (BayerUnify) method to unify different Bayer patterns. This allows us to fully utilize a heterogeneous dataset to train a single denoising model instead of training one model for each pattern. Furthermore, while it is essential to augment the dataset to improve model generalization and performance, we discovered that it is error-prone to modify raw images by adapting augmentation methods designed for RGB images. Towards this end, we present a Bayer preserving augmentation (BayerAug) method as an effective approach for raw image augmentation. Combining these data processing technqiues with a modified U-Net, our method achieves a PSNR of 52.11 and a SSIM of 0.9969 in NTIRE 2019 Real Image Denoising Challenge, demonstrating the state-of-the-art performance. Our code is available at https://github. com/Jiaming-Liu/BayerUnifyAug.

Recent years have witnessed a rapid accumulation of investigations on TiO2-based photocatalysis, which poses as a greatly promising advanced oxidation technology for water purification. As the ability of this advanced oxidation process is well demonstrated in lab and pilot scales to decompose numerous recalcitrant organic compounds and microorganism as well in water, further overpass of the hurdles that stand before the real application has become increasingly important. This review focuses on the fundamentals that govern the actual water purification process, including the fabrication of engineered TiO2-based photocatalysts, process optimization, reactor design, and economic consideration. The state of the art of photocatalyst preparation, strategies for process optimization, and reactor design determines the enhanced separation of photo-excited electron-hole (e-h) pairs on the TiO2surface. For the process optimization, the kinetic analysis including the rate-determining steps is in need. For large-scale application of the TiO2-based photocatalysis, economics is vital to balance the fundamentals and the applied factors. The fundamentals in this review are addressed from the perspective of a bridge to the real applications. This review would bring valuably alternative paradigm to the scientists and engineers for their associated research and development activities with an attempt to push the TiO2-based photocatalysis towards industrially feasible applications.

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