No abstract

Three phase (CB + BT)/PVDF composites with enhanced absorption properties have been synthesized. The results indicate that the maximum reflection loss can reach −38.8 dB at 9.2 GHz; the enhancement mechanism was explained.

Chainlike nickel nanostructures were prepared by using an efficient wet chemical method, and Ni/polyvinylidene fluoride (PVDF) composites were fabricated with a rotational orientation in a static magnetic field. The oriented magnetic nanochains in the composites show a uniform distribution without significant agglomeration, which favors the impedance matching and attenuation ability of the absorbents. The Ni/PVDF composite with only a 20 wt % loading of oriented nickel chains exhibits a minimum reflection loss (RL) value of −36.8 dB at 23.2 GHz from 18 to 26.5 GHz, while an optimal RL of −37.3 dB is obtained at 35.6 GHz with a 10 wt % loading from 26.5 to 40 GHz. Moreover, an excellent electromagnetic interference shielding effectiveness (35 dB) is achieved with an oriented filler loading of 30 wt %. Rotational orientation is an effective strategy for magnetic materials to achieve enhancements in both microwave absorption and shielding performance.

Purpose The online direct selling mode has been widely accepted by enterprises in the O2O era. However, the dual-channel (online/offline, forward/backward) operations of the closed-loop supply chain (CLSC) changed the relationship between manufacturers and retailers, thus resulting in channel conflict. The purpose of this paper is to take a dual-channel operations of CLSC as the research target, where a manufacturer sells a single product through a direct e-channel as well as a conventional retail channel; the retailer are responsible for collecting used products in the reverse supply chain and the manufacturer are responsible for remanufacturing. Design/methodology/approach The authors build a benchmark model of dual-channel price and service competition and take the return rate, which is considered to be related to the service level of the retailer, as the function of the service level to extend the model in the reverse SC. The authors then analyze the optimal pricing and service decision under centralization and decentralization, respectively. Finally, with the revenue-sharing factor, wholesale price and recycling price transfer payment coefficient as contract parameters, the paper also designs a revenue-sharing contract led by the manufacturer and explores in what situation the contract could realize the Pareto optimization of all players. Findings In the baseline model, the results show that optimal price and service level correlate positively in centralization; however, the relation relies on consumers’ price sensitivity in decentralization. In the extension model, the relationship between price and service level also relies on the relative value of increased service cost and remanufacturing saved cost. When the return rate correlates with the service level, a recycling transfer payment can elevate the service level and thus raise the return rate. Through analyzing the parameters in revenue-sharing contract, a point can be reached where lowering the wholesale price and raising the transfer payment coefficient will promote retailers to share revenue. Practical implications Many enterprises establish the dual-channel distribution system both online and offline, which need to understand how to resolve their channel conflict. The conflict is especially strong in CLSC with remanufacturing. The result helps the node enterprises realize the coordination of the dual-channel CLSC. Originality/value It takes into account the fact that there are two complementary relationships, such as online selling and offline delivery; used product recycling and remanufacturing. The authors optimize the strategy of product pricing and service level in order to solve channel conflict and double marginalization in the closed-loop dual-channel distribution network.

The minimum reflection loss of Fe3O4@SiO2@RGO nanocomposites can reach −26.6 dB at 9.7 GHz with low filler content; the mechanism was also explained.