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Hai‐Nan Lightning Detection Network (HNLDN) is composed of seven sites that accept very low frequency/low frequency (VLF/LF) signals. A total of seven sites are evenly distributed on Hai‐Nan Island. The baseline distance is between 50 and 150 km, which is about five times longer than in typical short‐baseline VLF/LF imaging networks. Each detection station uses zero‐phase digital filtering to avoid the phase deviation caused by filtering. HNLDN uses an improved peak search method to increase the number of detected of lightning waveforms, applies a One‐dimensional convolutional neural network (1D‐CNN) to identify and classify the waveforms, and to the increase the detection efficiency of intracloud lightning. This article analyzes three typical thunderstorm processes. From inside to outside the network, the detection efficiency of HNLDN relative to the advanced direction‐time lightning detection system (ADTD) is 239%, 181%, and 19%, respectively. It can be seen that the detection efficiency is negatively correlated with the distance from the thunderstorm to HNLDN. The average location error of HNLDN inside the network is 190 m. Key Points: Use very low frequency/low frequency network locationDepiction of a wide range of lightning in spaceThe new method improves the detection efficiency of cloud lightning and increases the number of lightning locations [ABSTRACT FROM AUTHOR]

One of the NHC–iridium coordination assemblies containing 1,5‐cyclooctadiene (COD) and iodide ion has been demonstrated as robust, efficient, recyclable solid molecular catalyst for N‐formylation of diverse primary and secondary amines with CO2 and H2 under mild reaction conditions. Remarkably, in the case of N,N‐dimethylformamide production, even at 0.1 mol % catalyst loading under solvent‐free conditions, the solid catalyst can be readily recovered by simply filtration and reused more than 10 runs without noticeable loss of activity. One of the NHC–iridium coordination assemblies containing 1,5‐cyclooctadiene (COD) and iodide ion has been demonstrated as a robust, efficient and recyclable solid molecular catalyst for N‐formylation of various primary and secondary amines with H2 and CO2 under mild reaction conditions at catalyst loadings as low as 0.1 mol %. [ABSTRACT FROM AUTHOR]

Abstract: By using the commercially available ruthenium pincer complex (Ru‐MACHO‐BH) as a catalyst, the challenging direct hydrogenation of lactams and analogues has been successfully accomplished to deliver corresponding value‐added amino alcohols in good‐to‐excellent yields under mild reaction conditions. Remarkably, in addition to N‐protected lactams, unprotected ones could also be readily reduced in the presence of a catalytic amount of weak base or even under neutral reaction conditions, which further highlights the broad substrate scope and the protocol efficiency. [ABSTRACT FROM AUTHOR]