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Clustering is an important research field in data mining.Based on dynamical synchronization model,an efficient synchronization clustering algorithm ESYN is proposed.Firstly,based on local structure information of a non-vector network,a new concept vertex similarity is brought up to describe the link density between vertices.Secondly,the network is vectoried by OPTICS algorithm and turned into one-dimensional coordination sequence.Finally,global coupling analysis is applied to generalized Kuramoto synchronization model,synchronization radius is increased and the optimal clustering result is automatically selected.The experimental results on a large number of synthetic and real-world networks show that proposed algorithm achieves high accuracy.

Abstract: CO2 is an attractive renewable C1 feedstock owing to its abundance, low cost, and nontoxicity. Developing new catalytic protocols for CO2 utilization is of great importance. With the development of photoredox catalysis over the past decades, light‐driven CO2 fixation has attracted significant attention. This Review will focus on recent development of light‐promoted carboxylation utilizing CO2 as a C1 source to synthesize value‐added chemicals in the area of organic synthesis. [ABSTRACT FROM AUTHOR]

Based on the wear resistance application scenarios of the heat surface tubes, fans and other components of popwer station boiler, coatings were prepared on the substrate 20G steel by high velocity arc - spraying technology with the application of two kinds of FeCr - based coating materials containing different carbon and rare earth element contents. Subsequently, the microscopic morphology and phase composition of the coatings were characterized through optical microscope (OM), scanning electron microscope (SEM), X - ray diffractometer (XRD) and white light interferometer system, and the mechanical and wear resistance properties of the coatings were tested through Vickers microhardness, tensile bonding strength, ball - disk friction and wear tests. Results showed that the microstructure of these two coatings was a typical lamellar structure. As B, C and other hard phase elements were distributed in FeCr solid solution, the microhardness of the coatings was much higher than that of the substrate. Furthermore, the high carbon content and the addition of rare earth elements contributed to a decrease of the porosity of the coatings from 2.22±0.47% to 0.92±0.13%, an increase of the microhardness from 8.05±0.53 GPa to 10.47±0.68 GPa, and a reduction of the wear weight loss by 40%. Judging from the wear morphology of the coatings, high microhardness and low porosity made the wear mechanism changed from adhesive wear to abrasive wear. In general, applying FeCr - based coatings to protect the wear surfaces could effectively solve the wear problem of the boiler parts of the power station, and thus ensure the safe and stable operation of the boiler units.