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We communicate a strategy for the hydrofunctionalization of 1,3-dienes via Rh-hydride catalysis. Conjugated dienes are coupled to nucleophiles to demonstrate the feasibility of novel C-C, C-O, C-S, and C-N bond forming processes. In the presence of a chiral JoSPOphos ligand, hydroamination generates chiral allylic amines with high regio- and enantioselectivity. Tuning both the pKa and steric properties of an acid-additive is critical for enantiocontrol.

Wind tunnel test results of the aerodynamic coefficients of sector-shape iced eight bundle conductors varying with wind attack angles are presented. Then, by means of the user-defined cable elements, the aerodynamic loads are applied on the cable elements of each sub-conductor through the finite element method (FEM). In addition, the galloping responses of sectorshape iced eight bundle conductors are discussed. Finally, galloping responses, including dynamic responses (natural modes and frequencies), galloping orbits, and amplitudes of typical sector-shape iced eight bundle conductor transmission lines in the cases of different span lengths, wind velocities, and angles of wind attack are studied, respectively. These results provide useful references for a theoretical basis for the study of galloping and the technique of anti-galloping in cold regions. Key words: sector-shape ice, eight bundle conductors, aerodynamic characteristics, wind tunnel test, finite element method (FEM). Les resultats des essais en soufflerie des coefficients aerodynamiques d'un groupe de huit conducteurs couverts de glace variant en fonction des angles d'attaque du vent sont presentes. Ensuite, au moyen des elements de cable definis par l'utilisateur, les charges aerodynamiques sont appliquees sur les elements de cable de chaque sous-conducteur par la methode des elements finis (FEM). De plus, la reponse galopante du groupe de huit conducteurs couverts de glace est discutee. Enfin, les reponses galopantes, y compris les reponses dynamiques (modes et frequences naturels), les orbites galopantes et les amplitudes des lignes de transmission types d'un groupe de huit conducteurs couverts de glace dans les cas de differentes longueurs de portee, vitesses du vent et angles d'attaque du vent sont etudies, respectivement. Ces resultats procurent des references utiles pour une base theorique dans le cadre de l'etude du galop et la technique anti- galop dans les regions froides. [Traduit par la Redaction] Mots-cles : glace formee sur un secteur, groupe de huit conducteurs, caracteristiques aerodynamiques, essai en soufflerie, methode des elements finis (FEM)., 1. Introduction Eight bundle conductor 1000 kV ultrahigh voltage (UHV) transmission lines have been launched to solve the imbalance problem between electric power supply and demand. Because of the complexity [...]

Unraveling the origin of Helmholtz capacitance is of paramount importance for understanding the interfacial structure and electrostatic potential distribution of electric double layers (EDL). In this work, we combined the methods of ab initio molecular dynamics and classical molecular dynamics and modeled electrified Cu(100)/electrolyte and graphene/electrolyte interfaces for comparison. It was proposed that the Helmholtz capacitance is composed of three parts connected in series: the usual solvent capacitance, water chemisorption induced capacitance, and Pauling repulsion caused gap capacitance. We found the Helmholtz capacitance of graphene is significantly lower than that of Cu(100), which was attributed to two intrinsic factors. One is that graphene has a wider gap layer at interface, and the other is that graphene is less active for water chemisorption. Finally, based on our findings, we provide suggestions for how to increase the EDL capacitance of graphene-based materials in future work, and we also suggest that the new understanding of the potential distribution across the Helmholtz layer may help explain some experimental phenomena of electrocatalysis. [ABSTRACT FROM AUTHOR]

The electrical resistivity method is widely used in near-surface mineral exploration. At present, the deterministic algorithm is commonly employed in three-dimensional (3-D) electrical resistivity inversion to obtain subsurface electrical structures. However, the accuracy and efficiency of deterministic inversion rely on the initial model. In practice, obtaining an initial model that approximates the true subsurface electrical structures remains challenging. To address this issue, we introduce a broad learning (BL) network to determine the initial model and utilize the limited memory quasi-Newton (L-BFGS) algorithm to conduct the 3-D electrical resistivity inversion task. The powerful mapping capability of the BL network enables one to find the model that elucidates the actual observed data. The single-layer BL network makes it efficient and easy to realize, leading to much faster network training compared to that using the deep learning network. Both the synthetic and field experiments suggest that the BL framework could effectively obtain the initial model based on observed data. Furthermore, in comparison to using a homogeneous medium as the initial model, the L-BFGS inversion with the BL framework-designed initial model improves the inversion accuracy of subsurface electrical structures and expedites the convergence speed of the iteration. This study provides an effective approach for fast initial model design in a data-driven manner when the prior information is unavailable. The proposed method can be useful in high-precision imaging of near-surface mineral electrical structures. [ABSTRACT FROM AUTHOR]