This article reports a particle image velocimetry study and the comparative results of a numerical simulation into the hydrodynamic characteristics around an artificial reef.We reveal the process of flow separation an...This article reports a particle image velocimetry study and the comparative results of a numerical simulation into the hydrodynamic characteristics around an artificial reef.We reveal the process of flow separation and vortex evolution,and compare the force terms generated by our artificial reef model.The numerical simulation agrees well with experimental results,showing the applicability of computational fluid dynamics to the hydrodynamics of an artificial reef.Furthermore,we numerically simulate the hydrodynamics of the reef model for seven velocities.The results show that the drag coefficient is approximately 1.21 in a self-modeling region for Reynolds numbers between 2.123×104and 9×104.Therefore,the upwelling height and current width of the flow field do not change significantly when the inflow velocity increases.Our study indicates that computational fluid dynamics can be applied to study the hydrodynamics of an artificial reef and offer clues to its construction.展开更多
In situ attenuated total refletion-Fourier transform infrared spectroscopy（ATR-FTIR） was used to monitorand acquire spectral information on the synthesis of 4-amino-3,5-dimethyl pyrazole. Principal component analy-...In situ attenuated total refletion-Fourier transform infrared spectroscopy（ATR-FTIR） was used to monitorand acquire spectral information on the synthesis of 4-amino-3,5-dimethyl pyrazole. Principal component analy-sis（PCA） was used to determine the number of principle components（PCs）. The score vectors of the PCs were ana-lysed using the simple-to-use interactive self-modelling mixture analysis（SIMPLISMA） algorithm to obtain spectraland concentration profiles for the reactants, intermediates and product. The vibrational frequencies of the interme-diates were calculated via density ftmctional theory（DFT） at the level of the B3LYP/6-31 l＋＋G（d,p） basis set, and thegeometrical configurations of the intermediates were simultaneously optimized. Finally, a reasonable synthesismechanism for 4-amino-3,5-dimethyl pyrazole was determined based on the changes observed in the feature peaks.The results from the SIMPLISMA algorithm correlated well with the quantttm chemistry calculations. This provedthat the SIMPLISMA algorithm combined with ATR-FTIR can be used to detemfine the synthesis mechanism for4-amino-3,5-dimethyl pyrazole and can even provide a new, useful method to explore dynamic synthesis reactionmechanisms.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31072246,31272703)
文摘This article reports a particle image velocimetry study and the comparative results of a numerical simulation into the hydrodynamic characteristics around an artificial reef.We reveal the process of flow separation and vortex evolution,and compare the force terms generated by our artificial reef model.The numerical simulation agrees well with experimental results,showing the applicability of computational fluid dynamics to the hydrodynamics of an artificial reef.Furthermore,we numerically simulate the hydrodynamics of the reef model for seven velocities.The results show that the drag coefficient is approximately 1.21 in a self-modeling region for Reynolds numbers between 2.123×104and 9×104.Therefore,the upwelling height and current width of the flow field do not change significantly when the inflow velocity increases.Our study indicates that computational fluid dynamics can be applied to study the hydrodynamics of an artificial reef and offer clues to its construction.
文摘In situ attenuated total refletion-Fourier transform infrared spectroscopy（ATR-FTIR） was used to monitorand acquire spectral information on the synthesis of 4-amino-3,5-dimethyl pyrazole. Principal component analy-sis（PCA） was used to determine the number of principle components（PCs）. The score vectors of the PCs were ana-lysed using the simple-to-use interactive self-modelling mixture analysis（SIMPLISMA） algorithm to obtain spectraland concentration profiles for the reactants, intermediates and product. The vibrational frequencies of the interme-diates were calculated via density ftmctional theory（DFT） at the level of the B3LYP/6-31 l＋＋G（d,p） basis set, and thegeometrical configurations of the intermediates were simultaneously optimized. Finally, a reasonable synthesismechanism for 4-amino-3,5-dimethyl pyrazole was determined based on the changes observed in the feature peaks.The results from the SIMPLISMA algorithm correlated well with the quantttm chemistry calculations. This provedthat the SIMPLISMA algorithm combined with ATR-FTIR can be used to detemfine the synthesis mechanism for4-amino-3,5-dimethyl pyrazole and can even provide a new, useful method to explore dynamic synthesis reactionmechanisms.
