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GIL/GIS bus is widely used in the field of power transmission and distribution, and the demand for lightweight is becoming more and more prominent. To reduce the weight of the bus and ensure the safety and reliability of the structure, a new 6σ robust design method of the GIL/GIS bus based on electric‐thermal‐mechanical co‐simulation is proposed. Taking a 550 kV/5000A bus as the initial structure, considering the uncertainty of product size and performance, a 6σ robust lightweight model of bus insulation electric field strength, current temperature rise, and mechanical stress multi‐performance co‐simulation is established. The finite element numerical calculation method is used to calculate and analyze the performance parameters of the bus. The Kriging surrogate model is used to form the response surface, and the optimal bus structure is obtained by genetic algorithm. The results show that after the robustness optimization, the performance of the bus meets the design requirements, the weight per meter decreased from 65.11 to 39.12 kg, and the lightweight effect is remarkable. Compared with the traditional deterministic optimization design, the reliability of the structure is improved. The new method of the GIL/GIS bus lightweight design proposed in this study has high feasibility and application prospects, which can provide new ideas for the development of gas‐insulated electrical equipment. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Risk communication involves conveying potential risks to the audience. It’s crucial for shaping behavior and influencing individual well-being. Previous research predominantly focused on verbal and written aspects of risk communication, with less emphasis on nonverbal cues like vocal tone. Addressing this gap, our study explores the impact of competent and warm vocal tones on risk communication across two risky decision-making paradigms, the Balloon Analogue Risk Task (BART) in Study 1 and the Gambling Task in Study 2. Results show that competent and warm vocal tones are more persuasive than neutral tones, and their effectiveness varies in different decision-making scenarios. Additionally, participants’ perceived competence and warmth of vocal tones mediate this persuasiveness. This study enhances our theoretical understanding of risk communication by incorporating the impact of vocal tones. Also, it carries practical implications for marketers and practitioners, demonstrating the importance of using voice as a medium to persuade in real-world scenarios. [ABSTRACT FROM AUTHOR]

In this paper, the problem of practical finite-time coordinated path following control of a multi-agent system in an uncertain Euler flow field is studied. The coordinated path following control system is decoupled into a path following sub-system and a coordinated formation sub-system. The uncertain Euler flow field is estimated by constructing an extended state observer. By embedding the extended state observer into the design of the finite-time controllers for both sub-systems, practical finite-time stability of the coordinated path following control system is proved. Simulation results are provided for validating the feasibility and effectiveness of the control method. [ABSTRACT FROM AUTHOR]

In order to explore the simulation method of the contact force for the ring-shaped spring and provide the support for the design of high-voltage switchgear-rated current and mechanical operating power, the parametric equation was derived, based on NX software the three-dimensional model was built, considering the influence of contact, friction, and large deformation, the non-linear dynamic finite element simulation model for the process of assembling and operating was established, the stress, resistance force, and friction force at any moment were obtained by simulation, and the variation of resistance and friction force during contact insertion was analysed. The results show that during the mechanical operating process, the resistance force rapidly increased to the extreme value and then gradually decreased to a stable value of 238N, and the friction force quickly increased and then slowly rose to the steady value of 238N, which is consistent with the experience and proved the rationality of the simulation model. Finally, according to the Coulomb friction law, the contact force of the spring contact was calculated as 1190N.

To reduce the operation power of the circuit breaker interrupter, here, the operation power is divided into two parts: the arc reaction force and kinetic energy of the moving parts, then the reaction force and the reactive force work calculation method are put forward. Based on the above method, the operating power of the original structure and the improved structure of the interrupter are obtained, and the comparison of the results shows that the improved structure can reduce the operating power.

A cobalt(II)‐catalyzed [4+2] annulation of picolinamides with alkynes via C−H bond activation has been developed. The operationally simple annulation reaction allows for the synthesis of acyl‐substituted 1H‐benzoquinoline bearing multiple aromatic rings (up to 96 % yield) without co‐oxidant or other oxidation factors under mild conditions. Several control experiments were carried out. This practical [4+2] annulation provides an efficient route to access highly functionalized compounds. [ABSTRACT FROM AUTHOR]

Water‐promoted palladium‐catalyzed asymmetric ring‐opening (ARO) reaction of oxabenzonorbornadienes with a wide variety of alkoxysilanes has been developed in a one‐pot fashion, yielding cis‐1,2‐dihydronaphthalen‐1‐ols in favourable yields (up to 98%) with gratifying enantioselectivities (up to 98% ee) under mild conditions. To the best of our knowledge, it represents the first example in the ring‐opening reactions of oxabicyclic alkenes with alkoxysilanes. Furthermore, the cis‐1,2‐configuration of product was established by X‐ray diffraction analysis, and a possible mechanism for the present catalytic ring‐opening reaction was also proposed. [ABSTRACT FROM AUTHOR]

A new iron(III)‐promoted reductive ring‐opening and isomerization reactions of C4‐alkynylisoxazoles in the oxidized N‐methylpyrrolidone (NMP*) was reported. By changing the substituents at the C3 and C5 position of the isoxazole ring, the reaction selectively produced 2‐alkynylenaminones and polysubstituted furans in good to excellent yields. It was very interesting that large group at the C3 or C5 position of the isoxazole ring was a steric hindrance tertiary butyl group (t‐Bu), the reaction proceeded ring‐opening rather than isomerization reaction in the presence of FeCl3. It was noteworthy that the NMP* as a solvent and a hydrogen donor was essential for both reactions. A plausible mechanism for the reductive ring‐opening and isomerization was also proposed. [ABSTRACT FROM AUTHOR]

The gas-insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability and environmental friendliness. It is suitable for the high voltage direct current (HVDC) power transmission of hydropower stations or nuclear power stations. However, due to the serious surface charge accumulation problem of the cone-type insulator under DC, its flashover performance is reduced, which restricts the engineering application of HVDC GIL. In this study, a charge transport model of SF6 gas and epoxy is established for a 550 kV cone-type insulator and the charge accumulation characteristics of the concave and convex surfaces of the cone-type insulator are obtained. Computational results show that the gas conductivity around the cone-type insulator is not uniform due to the charged particles drifting under a constant electric field. Compared with the AC, the difference of the electric field distribution caused by charge accumulation under DC stress is analysed. Based on the established model, the influence of the gas ion-pair generation rate and epoxy volume conductivity on the charge accumulation on the surface of 550 kV cone-type insulator was studied. This study is helpful to further optimise the geometry and material properties of the cone-type insulator and reduce the surface charge accumulation and critical area electric field to improve HVDC GIL insulation design. [ABSTRACT FROM AUTHOR]

An air‐promoted radical addition reaction of various thiols to oxa(aza)bicyclic alkenes is reported, leading to the corresponding exo adducts in good to excellent yields (up to 99%) in water without the use of any metal catalyst, photoredox catalyst or radical initiator reagent under mild conditions. The reaction has a wide scopeof oxa(aza)bicyclic alkenes and thiols, which provides an easy and clean way for the direct preparation of thioethers. A proposed mechanism of an exo free radical attacking the double bond of an oxa(aza)bicyclic alkene was investigated by DFT calculations of stepwise reaction pathways and control experiments. Something in the air: An air‐promoted radical addition reaction of thiols to oxa(aza)bicyclic alkenes is reported. The corresponding exo adducts are obtained in good to excellent yields (up to 99%) in water, without the use of any metal catalyst, photoredox catalyst or radical initiator reagent under mild conditions. A mechanism is also proposed, based on computational and experimental findings. [ABSTRACT FROM AUTHOR]

The Michael addition of malononitrile (II) to α,β-unsaturated pyrazolamides [(I), (IV), (VI), or (VIII), resp.] is accomplished by the use of bifunctional thioureas as catalysts. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed cycloaddition of diaryl disulfides to heterobicyclic alkenes has been developed. The C-S and C-C bonds can be formed simultaneously on the C═C bond of the olefins via a single-step cycloaddition to afford a series of 2,3-dihydrobenzo[b]thiophene derivatives. This reaction exhibits excellent diastereoselectivity and relatively broad substrate scope. Various functional groups attached to the substrates are tolerated in this protocol to give the corresponding exo adducts in moderate yields.

A novel copper-catalyzed complete diastereoselective 1,2-difunctionalization of oxabicyclic alkenes has been developed. Two C-S bonds were constructed simultaneously on the oxabenzonorbornadienes leading to β-thiocyanato thioethers through the three-component (oxabicyclic alkenes, aryl iodides, and potassium thiocyanate), one-pot reaction. Various functional groups attached to the substrates were tolerated in this protocol to afford the corresponding β-thiocyanato thioether products in moderate yields.

An efficient three-component cycloaddition of oxa(aza)bicyclic alkenes/norbornene in the presence of NaN 3 and arylsulfonyl chlorides was developed, affording the corresponding aziridine products in good yields (up to 82%) with moderate to good endo / exo selectivities (up to >99:1 endo / exo ). Further studies showed that the cycloaddition of oxa(aza)bicyclic alkenes in the presence of NaN 3 and chloroalkanes could afford the exo -cycloadduct 1,2,3-triazolines in good to excellent yields (up to 95%). Compared with the existing methodologies, the current protocol demands very simple and mild reaction conditions and is a metal-free catalyzed reaction. In addition, a plausible mechanism for the cycloaddition reaction was also proposed.

A novel ICl/AgNO 3 co-catalyzed radical oxidation of diaryl- and alkylarylalkynes into 1,2-diketones is reported. The reaction proceeded smoothly under mild conditions and generated 1,2-diketones in moderate to good yields with a good tolerance of functional groups. Furthermore, the obtained C4-(1,2-diketoaryl)isoxazoles could react smoothly with 1,2-diaminobenzene to form C4-(3-arylquinoxalin-2-yl)isoxazoles. At last, a new one-pot strategy for the synthesis of quinoxalines from 1,2-diphenylethynes and 1,2-diaminobenzene is also reported.