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Investigations into lithium–sulfur batteries (LSBs) has focused primarily on the initial conversion of lithium polysulfides (LiPSs) to Li2S2. However, the subsequent solid–solid reaction from Li2S2 to Li2S and the Li2S decomposition process should be equally prioritized. Creating a virtuous cycle by balancing all three chemical reaction processes is crucial for realizing practical LSBs. Herein, amorphous Ni3B in synergy with carbon nanotubes (aNi3B@CNTs) is proposed to implement the consecutive catalysis of S8(solid) → LiPSs(liquid) → Li2S(solid) →LiPSs(liquid). Systematic theoretical simulations and experimental analyses reveal that aNi3B@CNTs with an isotropic structure and abundant active sites can ensure rapid LiPSs adsorption‐catalysis as well as uniform Li2S precipitation. The uniform Li2S deposition in synergy with catalysis of aNi3B enables instant/complete oxidation of Li2S to LiPSs. The produced LiPSs are again rapidly and uniformly adsorbed for the next sulfur evolution process, thus creating a virtuous cycle for sulfur species conversion. Accordingly, the aNi3B@CNTs‐based cell presents remarkable rate capability, long‐term cycle life, and superior cyclic stability, even under high sulfur loading and extreme temperature environments. This study proposes the significance of creating a virtuous cycle for sulfur species conversion to realize practical LSBs. Virtuous cycle for consecutive electrocatalysis. Specifically, the binary sulfiphilic aNi3B with isotropic structure enables a rapid/uniform LiPSs adsorption. Meanwhile, the superior catalytic capability and ionic/electronic conductivity synergistically facilitated the fast/homogeneous Li2S precipitation. Uniform Li2S deposition helps fully oxidize it to LiPSs, which are quickly and uniformly adsorbed for the next sulfur evolution, creating a virtuous cycle for sulfur species conversion.

Two new low-voltage micropower first-order temperature-compensated CMOS current references are presented. To achieve compact architectures able to operate under low voltage with low power consumption, the references are based on the simplest approach of cross-coupled current mirrors, and compensation is obtained by introducing a temperature-dependent current mirror ratio. Results for 0.18 µm CMOS implementations show that the proposed 1 μA references operate with supplies down to 1 V showing temperature drifts below 231 ppm/°C over a (from –40 to 120°C) range.

Purpose To understand the behavior of the magnetization processes in ferromagnetic materials in function of temperature, a temperature-dependent hysteresis model is necessary. This study aims to investigate how temperature can be accounted for in the energy-based hysteresis model, via an appropriate parameter identification and interpolation procedure. Design/methodology/approach The hysteresis model used for simulating the material response is energy-consistent and relies on thermodynamic principles. The material parameters have been identified by unidirectional alternating measurements, and the model has been tested for both simple and complex excitation waveforms. Measurements and simulations have been performed on a soft ferrite toroidal sample characterized in a wide temperature range. Findings The analysis shows that the model is able to represent accurately arbitrary excitation waveforms in function of temperature. The identification method used to determine the model parameters has proven its robustness: starting from simple excitation waveforms, the complex ones can be simulated precisely. Research limitations/implications As parameters vary depending on temperature, a new parameter variation law in function of temperature has been proposed. Practical implications A complete static hysteresis model able to take the temperature into account is now available. The identification is quite simple and requires very few measurements at different temperatures. Originality/value The results suggest that it is possible to predict magnetization curves within the measured range, starting from a reduced set of measured data.