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11.
Sulfur hexafluoride (SF6) is considered as a potent greenhouse gas, whose effective degradation is challenging. Here we report a computational study on the nucleophilic activation of sulfur hexafluoride by N-heterocyclic carbenes and N-heterocyclic olefins. The result shows that the activation of SF6 is both thermodynamically and kinetically favorable at mild condition using NHOs with fluoro-substituted azolium and sulfur pentafluoride anion being formed. The Gibbs free energy barrier during the activation of SF6 has a linear relationship with the energy of HOMO of substrates, which could be a guideline for applying those compounds that feature higher energy in HOMO to activate SF6 in high efficiency. 相似文献
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S. Q. Hou W. Wang Z. Y. Wang Z. W. Hu K. Liu 《Journal of Applied Mechanics and Technical Physics》2018,59(1):153-162
In order to investigate the characteristics of force chains in a granular flow system, a parallel plate shear cell is constructed to simulate the shear movement of an infinite parallel plate and observe variations in relevant parameters. The shear dilatancy process is divided into three stages, namely, plastic strain, macroscopic failure, and granular recombination. The stickslip phenomenon is highly connected with the evolution of force chains during the shear dilatancy process. The load–distribution rate curves and patterns of the force chains are utilized to describe the load-carrying behaviors and morphologic changes of force chains separately. Force chains, namely, “diagonal gridding,” “tadpole-shaped,” and “pinnate” are defined according to the form of the force chains in the corresponding three stages. 相似文献
13.
Tuning the Basicity of Cyano‐Containing Ionic Liquids to Improve SO2 Capture through Cyano–Sulfur Interactions 下载免费PDF全文
Dr. Guokai Cui Fengtao Zhang Xiuyuan Zhou Prof. Haoran Li Prof. Jianji Wang Prof. Congmin Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5632-5639
A new approach has been developed to improve SO2 sorption by cyano‐containing ionic liquids (ILs) through tuning the basicity of ILs and cyano–sulfur interaction. Several kinds of cyano‐containing ILs with different basicity were designed, prepared, and used for SO2 capture. The interaction between these cyano‐containing ILs and SO2 was investigated by FTIR and NMR methods. Spectroscopic investigations and quantum chemical calculations showed that dramatic effects on SO2 capacity originate from the basicity of the ILs and enhanced cyano–sulfur interaction. Furthermore, the captured SO2 was easy to release by heating or bubbling N2 through the ILs. This efficient and reversible process, achieved by tuning the basicity of ILs, is an excellent alternative to current technologies for SO2 capture. 相似文献
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Hierarchical motion planning at the acceleration level based on task priority matrix for space robot
Nonlinear Dynamics - A capacitive micromachined ultrasonic transducer (CMUT) due to many benefits is being considered as an imaging and therapeutic technology recently. The critical challenge is to... 相似文献
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Xiaoshuang Luo Xinxian Qin Zhengyi Liu Dan Chen Weiwei Yu Kankan Zhang Deyu Hu 《Biomedical chromatography : BMC》2020,34(1):e4694
A simple and rapid analytical method for the detection of trifloxystrobin, trifloxystrobin acid and tebuconazole in soil, brown rice, paddy plants and rice hulls was established and validated by liquid chromatography with tandem mass spectrometry. Acceptable linearity (R2 > 0.99), accuracy (average recoveries of 74.3–108.5%) and precision (intra- and inter-day relative standard deviations of 0.9–8.8%) were obtained using the developed determination approach. In the field trial, the half-lives of trifloxystrobin and tebuconazole in paddy plants were 5.7–8.3 days in three locations throughout China, and the terminal residue concentrations of trifloxystrobin and tebuconazole were <100 and 500 μg/kg (maximum residue limits set by China), respectively, at harvest, which indicated that, based on the recommended application procedure, trifloxystrobin and tebuconazole are safe for use on rice. The risk assessment results demonstrated that, owing to risk quotient values of both fungicides being <100%, the potential risk of trifloxystrobin and tebuconazole on rice was acceptable for Chinese consumers. These data could provide supporting information for the proper use and safety evaluation of trifloxystrobin and tebuconazole in rice. 相似文献
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We propose a system of time-division multiplexing(TDM) and spatial frequency-division multiplexing(SFDM). Extrinsic Fabry–Perot interferometric sensors are applied to detect weak acoustic signals. The broadband source is employed, the light from it is modulated by a pulse signal sequence and is efficiently amplified by semiconductor optical amplifiers. Experimental results show that the equivalent noise pressure spectrum level is-97.2 d B re 1 rad/√Hz below 1250 Hz, and the cross talk between two sensors in one TDM channel is-32.7 d B with a cavity length difference of 60 μm. The number of sensors in this multiplexing system can theoretically reach 160. 相似文献