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Investigating the adsorption of organic pollutants onto boron nitride nanosheets is crucial for designing novel boron nitride adsorbents so as to remove pollutants from the environment. In this study, we performed density functional theory (DFT) computations to investigate the adsorption of 28 aromatic compounds onto boron nitride nanosheets, and developed four quantitative structure–activity relationship (QSAR) models for predicting the logarithm of the adsorption equilibrium constant (log  K ) values of organic pollutants adsorbed onto boron nitride nanosheets in both gaseous and aqueous environments. The DFT-predicted adsorption energies showed that boron nitride nanosheets exhibit stronger adsorption capability than graphene. Our QSAR analyses revealed that van der Waals interactions play dominant roles in gaseous adsorption, while van der Waals and hydrophobic interactions are the main driving forces in aqueous adsorption. This work demonstrates that in silico QSAR models can serve as efficient tools for high-throughput prediction of log  K values for organic pollutants adsorbed onto boron nitride nanomaterials. 

Abstract In this third paper of the series reporting on the reverberation mapping campaign of active galactic nuclei with asymmetric H β emission-line profiles, we present results for 15 Palomar–Green quasars using spectra obtained between the end of 2016–2021 May. This campaign combines long time spans with relatively high cadence. For eight objects, both the time lags obtained from the entire light curves and the measurements from individual observing seasons are provided. Reverberation mapping of nine of our targets has been attempted for the first time, while the results for six others can be compared with previous campaigns. We measure the H β time lags over periods of years and estimate their black hole masses. The long duration of the campaign enables us to investigate their broad-line region (BLR) geometry and kinematics for different years by using velocity-resolved lags, which demonstrate signatures of diverse BLR geometry and kinematics. The BLR geometry and kinematics of individual objects are discussed. In this sample, the BLR kinematics of Keplerian/virialized motion and inflow is more common than that of outflow.