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The future application of Li metal batteries (LMBs) at scale demands electrolytes that endow improved performance under fast-charging and low-temperature operating conditions. Recent works indicate that desolvation kinetics of Li+ plays a crucial role in enabling such behavior. However, the modulation of this process has typically been achieved through inducing qualitative degrees of ion pairing into the system. In this work, we find that a more quantitative control of the ion pairing is crucial to minimizing the desolvation penalty at the electrified interface and thus the reversibility of the Li metal anode under kinetic strain. This effect is demonstrated in localized electrolytes based on strongly and weakly bound ether solvents that allow for the deconvolution of solvation chemistry and structure. Unexpectedly, we find that maximum degrees of ion pairing are suboptimal for ultralow temperature and high-rate operation and that reversibility is substantially improved via slight local dilution away from the saturation point. Further, we find that at the optimum degree of ion pairing for each system, weakly bound solvents still produce superior behavior. The impact of these structure and chemistry effects on charge transfer are then explicitly resolved via experimental and computational analyses. Lastly, we demonstrate that the locally optimized diethyl ether-based localized-high-concentration electrolytes supports kinetic strained operating conditions, including cycling down to -60 °C and 20-min fast charging in LMB full cells. This work demonstrates that explicit, quantitative optimization of the Li+ solvation state is necessary for developing LMB electrolytes capable of low-temperature and high-rate operation.

Antenna design and optimization must ensure robust electrical performance, making its analysis a crucial step in all antenna design processes. Traditionally, this analysis involves setting up various cases after establishing the calculation model, comparing the performance of each case, and summarizing the impact of relevant factors to guide design and optimization. However, this method is time-consuming and inefficient. This paper proposes a sensitivity-based approach for analyzing antenna electrical performance, using a radome-covered array antenna as an example. First, we derive the formulas for calculating the antenna's electrical performance and its sensitivity to the current amplitude, array element position, and radome thickness. We then design comparative experiments to analyze the antenna's performance using the sensitivity-based method and the traditional case enumeration method. Comparing the conclusions of both methods, we find that they yield the same results regarding antenna performance. The proposed sensitivity-based method offers a quantitative evaluation of various influencing factors and provides a more scientific and systematic approach to analyzing antenna electrical performance. [ABSTRACT FROM AUTHOR]

To address the issues of corrosion weakening of solid-waste-based backfill material caused by mine water, a novel hydrophobic solid waste backfill (HSBF) material was developed using polydimethylsiloxane (PDMS) and a silane coupling agent (SCA) as hydrophobic modification additives, and NaOH (SH) and sodium silicate (SS) as alkali activators. Fly ash and slag were chosen as the primary raw solid waste materials. The rheological properties of the hydrophobic-treated backfill slurries were measured, and the resulting physicochemical properties were compared with the unmodified reference group. This study reveals that the fresh HSBF slurry follows a Modified Bingham (M-B) model with shear-thinning characteristics. The addition of PDMS causes an increase in the water contact angle of the hardened HSBF material with F8S2 to up to 134.9°, indicating high hydrophobicity. Morphological observations indicated that PDMS mainly attaches to the inorganic particles' surface through the bridging action of SCA for the hydrophobic modification of the backfill material. The overall strength of the HSBF materials was further ensured via fly ash–slag ratio optimization, and was found to be enhanced up to 98% by increasing slag content from 20% to 50%. This is mainly attributed to the hydration of slag, forming C-S(A)-H gel, which contributes to the increased strength. The novel HSBF material enables the elimination of cement in mine backfilling applications, demonstrating good economic benefits. Its excellent mechanical and hydrophobic properties can not only prevent overburden displacement in goaf areas, but can also mitigate water resource loss from overlying strata and simultaneously reduce the safety risks associated with long-term mine water deterioration. [ABSTRACT FROM AUTHOR]

The utilization of CO2 mineralization fly ash (F) and coal gangue (G) technology is proposed in this research work to prepare underground backfilling materials. The test process can be divided into pre-treatment and post-treatment stages. In the pre-treatment stage, a sealed stirring vessel is used to conduct CO2 wet mineralization. The ratios of F and G were selected as follows: 20%:60% (F2G6), 30%:50% (F3G5), 40%:40% (F4G4), 50%:30% (F5G3), and 60%:20% (F6G2). The ratios were prepared into Φ50 mm × 100 mm cylindrical samples, with curing durations of 3 d, 7 d, 14 d, and 28 d. In the post-processing stage, the SANS microcomputer-controlled electronic universal testing machine and FLIR A615 infrared thermal imager were used to carry out uniaxial loading and temperature detection, respectively. The unconfined compressive strength (UCS), X-ray diffraction (XRD), average infrared radiation temperature (AIRT), variance of original infrared image temperature (VOIIT), and variance of successive minus infrared image temperature (VSMIT) of the samples were compared and analyzed. The results indicated that when curing reaches 14 d, the strength approaches its peak, with minimal changes in strength over a delayed period; furthermore, as the ratio of F to G continues to increase, the mineralization effect gradually strengthens, reaching its optimum level at a ratio of 5:3. However, when the ratio exceeds 5:3, signs of deteriorating mineralization effect start to appear. During the loading process, the AIRT of the mineralized samples showed a continuous increase, but the VOIIT and VSMIT of the mineralized sample both exhibited significant fluctuations or rapid increases during damage rupture. Moreover, the rise in the AIRT value was found to be linked to the increase in the ratio of F to G. This indicates that F has a higher thermal–mechanical conversion efficiency compared to G, so the temperature change will be greater during the loading process. The drastic changes in the VOIIT and VSMIT indicate that they can be used as sensitive response indicators for sample rupture, and can predict and warn of damage rupture in mineralized samples. Research work can provide practical guidance and reference for underground backfilling of CO2 mineralization industrial waste. [ABSTRACT FROM AUTHOR]

Partner selection is the primary aspect of the formation of knowledge collaboration teams (KCTs). We propose a method of partner selection for KCTs based on a weighted social network analysis (SNA) method in which the individual knowledge competence and the collaboration performance of candidates are both considered. To select the desired partners, a biobjective 0-1 model is built, integrating the knowledge competence and collaboration performance, which is an NP-hard problem. Then, a multiobjective genetic algorithm (MOGA) is developed to solve the proposed model. Finally, a real-world example is provided to illustrate the applicability of the model, and the MOGA is implemented to search for Pareto solutions of partner selection for KCT in this case. Moreover, some simulation examples are used to test the efficiency of the algorithm. The results suggest that the proposed method can support effective and practical partner selection.

Particle damping technology, which was developed from impact damping technology, has been successfully used in many fields for vibration reduction. However, the vibration reduction effect of a particle damper (PD) under centrifugal loads is poor and there have been few studies about it. Therefore, a particle damper under rotational conditions was modeled and the effect of the cavity was investigated in this paper. The cavity of the PD is a circular hole. The relationship of the normal pressure between particle layers and the depth in different orientations of the hole under centrifugal loads was established based on powder and soil mechanics. Moreover, the discrete element method was used to simulate the particle damper. In the conditions of rotation, the effects of the orientation and aspect ratio of the PD’s hole on the vibration reduction were studied. Results showed that the hole of the PD drilled perpendicular to the centrifugal load achieved better damping effect and a slender hole (the length is larger than the diameter) provided better vibration reduction effect. In addition, as the rotation speed increased, the optimal aspect ratio also increased. The results can be used as a guide in the design of particle dampers under rotational conditions. [ABSTRACT FROM AUTHOR]