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Due to the synergistic effect between multiple elements, bimetallic selenides materials can generate more active sites in the electrochemical reaction process, which can significantly improve the electrical conductivity for anode materials. Nevertheless, it is liable to produce severe volume expansion and exhibit the poor electrochemical performance. Therefore, we decided to modify it by carbon cladding; the carbon-coated short rod-like NiCoSe2 (NiCoSe2@C) nanomaterials were synthesized through facile hydrothermal reaction, dopamine coating, and carbonization process. It was found that the as-prepared NiCoSe2@C nanomaterial exhibits stable structure, outstanding cycling stability, and high pseudocapacitive contribution. Specifically, the specific charging capacity is 370.6 mAh g−1 (0.1 A g−1, 100 cycles) and 304.8 mAh g−1 (2 A g−1, 600 cycles) as anode when used for SIBs. Comparing with the pure NiCoSe2 nanomaterial, the construction of carbon layer can mitigate the effect of volume expansion and reduce the generation of adverse materials, thus enhancing the cycling stability. [ABSTRACT FROM AUTHOR]

Propargylic amines are versatile synthetic intermediates in organic synthesis and can be readily accessed through a catalytic three-component coupling of aldehydes, alkynes, and amines, termed the "A SP 3 sp coupling". [33] Moreover, reactions of propargylic amine substrates B 1n b and B 1o b bearing alternative amine moieties also proceeded smoothly (Scheme 3). Keywords: 2-boryl allylboronates; propargylic amines; platinum catalysis; bimetallic synergistic effect; diborylation EN 2-boryl allylboronates propargylic amines platinum catalysis bimetallic synergistic effect diborylation 1573 1576 4 07/31/23 20230815 NES 230815 Graph Organoboron compounds play essential roles in organic synthesis and in the pharmaceutical industry. [Extracted from the article]

Accurate granularity estimation of ore images is vital in automatic geometric parameter detecting and composition analysis of ore dressing progress. Machine learning based methods have been widely used in multi-scenario ore granularity estimation. However, the adhesion of coal particles in the images usually results in lower segmentation accuracy. Because much powdery coal fills between blocky ones, making edge contrast between them is not distinct. Currently, the coal granularity estimation is still carried out empirical in nature. We propose a novel method for coal granularity estimation based on a deep neural network called Res-SSD to deal with the problem. Then, to further improve the detection performance, we propose an image enhancement layer for Res-SSD. Since the dust generated during production and transportation will seriously damage the image quality, we first propose an image denoising method based on dust modelling. By investigating imaging characteristics of coal, we second propose the optical balance transformation(OBT), by which the distinguishability of coal in dark zones can be increased. Meanwhile, OBT can also suppress overexposed spots in images. Experimental results show that the proposed method is better than classic and state-of-the-art methods in terms of accuracy while achieving a comparable speed performance. [ABSTRACT FROM AUTHOR]

The cyclopropanation of alkenes through the transition-metal-catalyzed decomposition of diazo compounds is a powerful and straightforward strategy to produce cyclopropanes. Nevertheless, the appeal of further application of this strategy is tempered by the potentially explosive nature of the diazo substrates. Therefore, it is highly desirable to develop sustainable and operationally safe surrogates for diazo compounds. In this Synpacts article, we discuss recent advances on the cyclopropane syntheses through the catalytic cyclopropanation of alkenes and metal carbenes generated in situ from nondiazo precursors as well as highlight our recent progress on the unprecedented molybdenum-catalyzed deoxygenative cyclopropanation reaction of 1,2-dicarbonyl or monocarbonyl compounds. [ABSTRACT FROM AUTHOR]

Precipitation has been suggested as a crucial influencing factor in the primary productivity in arid and semi-arid regions, yet how moisture fluctuation in an arid mountain-basin system of the north Qinghai–Tibetan Plateau has affected human activities is poorly understood. Here, we reconstruct the variations of grazing intensity in high elevations and regional humidity based on independent and high-resolution records of Sporormiella -type coprophilous fungal spores and pollen grains in the same well-dated sediment core from Lake Tian'E in the western Qilian Mountains over the past 3500 years. We find that stronger grazing activity was associated with low regional effective moisture, and propose that the drier regional climate pushed people and their livestock into the mountainous areas. A notable exception was a reduction of human and grazing activities in arid region with high mountains during 380–580 CE caused by centennial-length dry and cold conditions. In addition, it is also noteworthy that intensified grazing activity occurred during 580–720 CE and after ∼1920 CE, corresponding to a warmer and wetter climate and diverse subsistence strategies with social developments in the lowlands of the Hexi Corridor. Our findings potentially provide a historical reference for understanding how ancient people adapted to the climate change in arid region with high mountains. [ABSTRACT FROM AUTHOR]