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The HSAB principle in designing Bis(imino)acenaphthene N‐heterocyclic carbene (NHC) palladium complexes is presented. N‐donor ligands serve as hard bases to enhance the catalytic activities of NHC Pd complexes in Suzuki and Buchwald–Hartwig amination reactions. The Pd complex bearing tertiary amine ligands exhibited higher performance in coupling reactions than those exhibited by other soft base ligands reported in literature. 48 coupling products were generated in moderate‐to‐complete yields in the presence of aryl chlorides as substrates for Suzuki and amination reactions in air under mild conditions. [ABSTRACT FROM AUTHOR]

Less-frequent and inadequate sampling of sediment data has negatively impacted the long and continuous records required for the design and operation of hydraulic facilities. This data-scarcity problem is often found in most river basins of Taiwan. This study aims to propose a parsimonious probabilistic model based on copulas to infill daily suspended sediment loads using streamflow discharge. A copula-based bivariate distribution model of sediment and discharge of the paired recorded data is constructed first. The conditional distribution of sediment load given observed discharge is used to provide probabilistic estimation of sediment loads. In addition, four different methods based on the derived conditional distribution of sediment load are used to give single-value estimations. The obtained outcomes of these methods associated with the results of the traditional sediment rating curve are compared with recorded data and evaluated in terms of root mean square error (RMSE), mean absolute percentage error (MAPE), Nash-Sutcliffe efficiency (NSE), and modified Nash-Sutcliffe efficiency (MNSE). The proposed approach is applied to the Janshou station located in eastern Taiwan with recorded daily data for the period of 1960–2019. The results indicate that the infilled sediments by the sediment rating curve exhibit better performance in RMSE and NSE, while the copula-based methods outperform in MAPE and MNSE. Additionally, the infilled sediments by the copula-based methods preserve scattered characteristics of observed sediment-discharge relationships and exhibit similar frequency distributions to that of recorded sediment data. [ABSTRACT FROM AUTHOR]