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101.
A novel, rational‐designed approach to access various heteroaryl‐substituted alkyl thioethers was developed via docking‐migration cascade process. By utilizing three components involving alkene, dual‐function reagent, and thioetherificating reagent, radical heteroarylalkylation of alkenes followed by thiolation of the alkyl radical intermediates proceeded smoothly, manifesting well compatibility of substrates and cascade transformations. Furthermore, this protocol also features mild conditions, broad substrate scope, and wide product diversity. 相似文献
102.
Sha Xia Dan Wang Nian-Ke Chen Dong Han Xian-Bin Li Hong-Bo Sun 《Annalen der Physik》2020,532(3):1900318
Defects play a central role in controlling the electronic properties of two-dimensional (2D) materials and realizing the industrialization of 2D electronics. However, the evaluation of charged defects in 2D materials within first-principles calculation is very challenging and has triggered a recent development of the WLZ (Wang, Li, Zhang) extrapolation method. This method lays the foundation of the theoretical evaluation of energies of charged defects in 2D materials within the first-principles framework. Herein, the vital role of defects for advancing 2D electronics is discussed, followed by an introduction of the fundamentals of the WLZ extrapolation method. The ionization energies (IEs) obtained by this method for defects in various 2D semiconductors are then reviewed and summarized. Finally, the unique defect physics in 2D dimensions including the dielectric environment effects, defect ionization process, and carrier transport mechanism captured with the WLZ extrapolation method are presented. As an efficient and reasonable evaluation of charged defects in 2D materials for nanoelectronics and other emerging applications, this work can be of benefit to the community. 相似文献
103.
Three mesoporous molecular sieves loaded silicotungstic acids, named HSiW/SBA-15, HSiW/MCM-41, HSiW/MCM-48, were prepared and characterised by XRD, FT-IR, TEM and SEM. The catalytic performance of the prepared materials for the Baeyer-Villiger oxidation of cyclic ketones was carried out in the presence of 30%H2O2 under mild conditions. These loading materials were proved to be efficient and reusable catalysts, they all exhibited excellent catalytic performance for the Baeyer-Villiger oxidation of cyclic ketones with 30% H2O2 as oxidant. Many cyclic ketones were efficiently converted to the corresponding lactones with up to 90% conversions and high selectivities under the optimum reaction conditions. Cyclic ketones were efficiently oxidised by mesoporous materials sopported silicotungstic acid to the corresponding lactones with 30%H2O2 as oxidant. All of the catalysts showed promising recyclability in the reactions. 相似文献
104.
Microstructure evolution and passivation quality of hydrogenated amorphous silicon oxide(a-SiOx:H) on〈100〉- and 〈111〉-orientated c-Si wafers 下载免费PDF全文
Hydrogenated amorphous silicon oxide(a-SiOx:H) is an attractive passivation material to suppress epitaxial growth and reduce the parasitic absorption loss in silicon heterojunction(SHJ) solar cells. In this paper, a-SiOx:H layers on different orientated c-Si substrates are fabricated. An optimal effective lifetime(τ(eff)) of 4743 μs and corresponding implied opencircuit voltage(iV(oc)) of 724 mV are obtained on〈100〉-orientated c-Si wafers. While τ(eff) of 2429 μs and iVoc of 699 mV are achieved on 111-orientated substrate. The FTIR and XPS results indicate that the a-SiOx:H network consists of SiOx(Si-rich), Si–OH, Si–O–SiHx, SiO2 ≡ Si–Si, and O3 ≡ Si–Si. A passivation evolution mechanism is proposed to explain the different passivation results on different c-Si wafers. By modulating the a-SiOx:H layer, the planar silicon heterojunction solar cell can achieve an efficiency of 18.15%. 相似文献
105.
106.
Meccanica - Based on the classification ability of a convolutional neural network (CNN), this paper proposes a structural damage detection method in which a CNN is used to classify the location and... 相似文献
107.
Nonlinear Dynamics - A trans-media aerial underwater vehicle (TMAUV) could break through the single-medium limitation with the abilities to fly in the air, navigate underwater, and cross the... 相似文献
108.
109.
Numerical Algorithms - Recursive blocked algorithms have proven to be highly efficient at the numerical solution of the Sylvester matrix equation and its generalizations. In this work, we show that... 相似文献
110.
Wenxiong Chen & Ruobing Zhang 《数学研究》2020,53(4):436-470
In this paper, we will explore the geometric effects of conformally covariant
operators and the induced nonlinear curvature equations in certain nonlocal nature.
Mainly, we will prove some regularity and rigidity results for the distributional solutions to those equations. 相似文献