Notably, 159 confirmed cases have been reported in 23 other countries beyond China, including Japan, Thailand, Singapore, South Korea, Australia, the USA, Malaysia, and Germany. Because of the ...seriousness of this outbreak, WHO declared it a public health emergency of international concern on Jan 30, 2020, followed by the USA announcing a public health emergency on Jan 31, 2020. ...it is important to understand the lung microenvironment and the map of immune responses against 2019-nCoV infection, which might help to define clinical stages and uncover the pathogenesis of the disease. First-line medical staff and scientists in China have had a leading role in fighting the outbreak of 2019-nCoV-associated pneumonia.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recently, a tensor nuclear norm (TNN) based method was proposed to solve the tensor completion problem, which has achieved state-of-the-art performance on image and video inpainting tasks. However, ...it requires computing tensor singular value decomposition (t-SVD), which costs much computation and thus cannot efficiently handle tensor data, due to its natural large scale. Motivated by TNN, we propose a novel low-rank tensor factorization method for efficiently solving the 3-way tensor completion problem. Our method preserves the low-rank structure of a tensor by factorizing it into the product of two tensors of smaller sizes. In the optimization process, our method only needs to update two smaller tensors, which can be more efficiently conducted than computing t-SVD. Furthermore, we prove that the proposed alternating minimization algorithm can converge to a Karush-Kuhn-Tucker point. Experimental results on the synthetic data recovery, image and video inpainting tasks clearly demonstrate the superior performance and efficiency of our developed method over state-of-the-arts including the TNN and matricization methods.
Terrestrial heat flow is a crucial parameter to indicate the thermal state within the Earth, containing integrated information of the ground temperature, thermal conductivity, and crustal/mantle heat ...flow. We present an updated heat flow dataset and map in continental China. The data increases from 862 to 1230 observations since the year 1999 and the sites cover the major tectonic units, although their spatial distribution remains uneven. Excluding the local anomalies related to hydrothermal activities, the background heat flow values display a range from 30 to 140 mW m–2 with a mean of 60.4 ± 12.3 mW m–2. The updated heat flow map exhibits a heat flow pattern consisted of four heat flow provinces in continental China: eastern mantle-induced high flow province, southwestern crust-induced high heat flow province, central normal heat flow province and northwestern low heat flow province. The major heat flow provinces correspond to the Cenozoic lithosphere-scale tectonic units. The heat flow shows good correlation with crustal thickness and elevation, agreeing with the thermal isostasy. The heat flow distribution also corresponds with the Meso-Cenozoic tectonic activities. The present heat flow-tectonic pattern in continental China is formed by the Meso-Cenozoic geodynamic processes, including the Cenozoic India-Eurasian collision and the Mesozoic-Cenozoic western subduction of the Pacific Plate.
•Update the heat flow data of the continental China•Discuss the heat flow characteristics of the various tectonic units•Reveal the heat flow distribution pattern of continental China
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, we give new necessary and sufficient conditions for the compactness of composition operator on the Besov space and the Bloch space of the unit ball, which, to a certain extent, ...generalizes the results given by M. Tjani in \cite{1}. KCI Citation Count: 0
Current mainstream single-object trackers adopt the Transformer as the backbone for target tracking. However, due to the Transformer's limitations in local information acquisition and position ...encoding, we proposed a new tracking framework called ConvFormer to enhance the model's performance. Our framework aims to improve the feature extraction ability by combining the local feature extraction ability of CNN with the global feature extraction ability of the Transformer. To achieve synchronous feature extraction and fusion of the template and search region, we propose Mix Net Module (MNM), which achieves both global and local feature extraction and fusion for the template and search regions. Based on MNM, we stacked MNM modules and added a location head to complete the construction of the ConvFormer framework. Moreover, we designed a post-processing module to reduce the impact of tracker mistracking and improve the model's robustness against interference from similar objects. Our framework achieved state-of-the-art performance on six benchmarks, including OTB2015, VOT2018, GOT-10k, LaSOT, TrackingNet, and UAV123. Notably, on the TrackingNet dataset, our tracker outperformed OSTrack by 1.4% with 83.2% precision. Additionally, on the LaSOT dataset, our tracker surpassed OSTrack by 2.6% with 77.4% precision. Finally, we conducted numerous ablation experiments to validate the efficacy of our approach.
Photocatalytic water splitting is promising for hydrogen energy production using solar energy and developing highly efficient photocatalysts is challenging. Defect engineering is proved to be a very ...useful strategy to promote the photocatalytic performance of metal‐based photocatalysts, however, the vital role of defects is still ambiguous. This work comprehensively reviews point defective metal‐based photocatalysts for water splitting, focusing on understanding the defects' disorder effect on optical adsorption, charge separation and migration, and surface reaction. The controllable synthesis and tuning strategies of defective structure to improve the photocatalytic performance are summarized, then the characterization techniques and density functional theory calculations are discussed to unveil the defect structure, and analyze the defects induced electronic structure change of catalysts and its ultimate effect on the photocatalytic activity at the molecular level. Finally, the challenge in developing more efficient defective metal‐based photocatalysts is outlined. This work may help further the understanding of the fundamental role of defect structure in the photocatalytic reaction process and guide the rational design and fabrication of highly efficient and low‐cost photocatalysts.
This work summarizes the role of defects in metal‐based materials for photocatalytic water splitting from an experimental and theoretical perspective. The fabrication and characterization methods of defective metal‐based photocatalysts are summarized. Defects induced electronic structure changes of catalysts and how they ultimately affect the reactivity are discussed. The challenges and outlook in developing defective metal‐based catalysts are also given.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The first example of PdII‐catalyzed enantioselective C−H olefination with non‐chiral or racemic sulfoxides as directing groups was developed. A variety of chiral diaryl sulfoxides were synthesized ...with high enantioselectivity (up to 99 %) through both desymmetrization and parallel kinetic resolution (PKR). This is the first report of PdII‐catalyzed enantioselective C(sp2)−H functionalization through PKR, and it represents a novel strategy to construct sulfur chiral centers.
A PdII‐catalyzed enantioselective C−H olefination with non‐chiral or racemic sulfoxides as directing groups was developed. A variety of chiral diaryl sulfoxides were synthesized with high enantioselectivity through both desymmetrization and parallel kinetic resolution (PKR). This is the first reported PdII‐catalyzed enantioselective C(sp2)−H functionalization through PKR, and it represents a novel strategy to construct sulfur chiral centers.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Electrocatalysis plays a central role in clean energy conversion, enabling a number of processes for future sustainable technologies. Atomic site electrocatalysts (ASCs), including single-atomic site ...catalysts (SASCs) and diatomic site catalysis (DASCs), are being pursued as economical alternatives to noble-metal-based catalysts for these reactions by virtue of their exceptionally high atom utilization efficiencies, well-defined active sites and high selectivities. In this review, we start from a systematic review on the fabrication routes of ASCs followed by an overview of some new and effective characterization methods to precisely probe the atomic structure. Then we give a comprehensive summary on the current advances in some typical clean energy reactions: water splitting, including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER); oxygen reduction reaction (ORR), including selective 4e
−
- ORR toward H
2
O/OH
−
and 2e
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- ORR toward H
2
O
2
/HO
2
−
; selective electrooxidation of formic acid, methanol and ethanol (FAOR, MOR and EOR). At the end of this paper, we present a brief conclusion, and discuss the challenges and opportunities on the further development of more selective, active, stable and less expensive ASCs.
This review summarized the fabrication routes and characterization methods of atomic site electrocatalysts (ASCs) followed by their applications for water splitting, oxygen reduction and selective oxidation.
Chemical modification of electrode materials by heteroatom dopants is crucial for improving storage performance in rechargeable batteries. Electron configurations of different dopants significantly ...influence the chemical interactions inbetween and the chemical bonding with the host material, yet the underlying mechanism remains unclear. We revealed competitive doping chemistry of Group IIIA elements (boron and aluminum) taking nickel‐rich cathode materials as a model. A notable difference between the atomic radii of B and Al accounts for different spatial configurations of the hybridized orbital in bonding with lattice oxygen. Density functional theory calculations reveal, Al is preferentially bonded to oxygen and vice versa, and shows a much lower diffusion barrier than BIII. In the case of Al‐preoccupation, the bulk diffusion of BIII is hindered. In this way, a B‐rich surface and Al‐rich bulk is formed, which helps to synergistically stabilize the structural evolution and surface chemistry of the cathode.
A model study has been performed on Group IIIA element (boron and aluminum) co‐doped high‐nickel layered oxide cathode materials to understand competitive doping chemistry. A notable difference between the atomic radii of B and Al accounts for different spatial configurations of the hybridized orbital in bonding with lattice oxygen, resulting in the formation of a B‐rich surface and an Al‐rich bulk.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The sigma (σ)‐hole effect has emerged as a promising tool to construct novel architectures endowed with new properties. A simple yet effective strategy for the generation of monofluoromethyl radicals ...is a continuing challenge within the synthetic community. Fluoromethylphosphonium salts are easily available, air‐ and thermally stable, as well as simple‐to‐handle. Herein, we report the ability of the σ‐hole effect to facilitate the visible‐light‐triggered photolysis of phosphonium iodide salts, a charge‐transfer complex, selectively giving fluoromethyl radicals. The usefulness and versatility of this new protocol are demonstrated through the mono‐, di‐, and trifluoromethylation of a variety of alkenes.
Simple and selective synthesis of fluoromethylated alkenes, heterocycles, enamines and heteroarenes by using the readily available and bench‐stable fluoromethylphosphonium iodide salts is described. Key to this privileged transformation is the formation of a photoactive charge‐transfer complex involving the σ‐hole effect of phosphonium salts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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