Silyl-phenanthroline (NN'Si) ligand ancillary iridium-catalyzed C(sp)-H borylation is investigated theoretically. Density functional theory calculations clearly disclose that the (NN'Si)Ir(H)(Bpin) (NN'Si = 6-[(di--butylsilyl)methyl]-1,10-phenanthroline) complex is a resting state, and the (NN'Si)Ir(Bpin) complex serves as an active species in the catalytic cycle. The remarkably high activity of this type of a catalyst arises from the rapid reductive elimination of HBpin from (NN'Si)Ir(H)(Bpin) to generate the active species (NN'Si)Ir(Bpin).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2019
The flexible Li-O battery is suitable to satisfy the requirements of a self-powered energy system, thanks to environmental friendliness, low cost, and high theoretical energy density. Herein, a flexible porous bifunctional electrode with both electrocatalytic and photocatalytic activity was synthesized and introduced as a cathode to assemble a high-performance Li-O battery that achieved an overpotential of 0.19 V by charging with the aid of solar energy.
View Article and Find Full Text PDFDust fall was selected as a monitored index of fugitive dust from construction sites. The vertical dispersion law of fugitive dust was studied nearby construction site's boundary by monitoring the concentration variation of dust fall at different heights from 1.5 meters to 4.
View Article and Find Full Text PDFHuan Jing Ke Xue
December 2007
More than forty construction sites were selected as experimental fields in urban districts and near suburbs of Beijing. Fugitive dust from construction sites was monitored by dust fall. The characteristics of fugitive dust pollution in different construction phases were studied.
View Article and Find Full Text PDFThis paper studied the correlation between dust fall and TSP from construction sites in Beijing by statistically analyzing a large number of field measurement data. The results show that there are better linear correlations between dust fall and TSP from construction fugitive dust, and the correlation between dust fall and TSP at construction sites' boundary can be expressed by the function: c(TSP) = 11.6 x c(DF).
View Article and Find Full Text PDF