Building Ion-Conductive Supramolecular Elastomeric Protective Layer via Dynamic Hard Domain Design for Stable Zinc Metal Anodes.

The instability of zinc metal anode caused by zinc dendrite growth and severe parasitic reactions has significantly restricted the extensive application of rechargeable aqueous zinc-ion batteries (RAZBs). Herein, based on the strategy of dynamic hard domains, we develop an ion-conductive supramolecular elastomer consisting of Zn salts and the polyurethane-urea-polypropylene glycol polymer skeleton. This elastomer combines high mechanical strength, high ionic conductivity, decent hydrophobicity, and high adhesion to stabilize the electrode-electrolyte interface. In the elastomer system, this elastomer can dynamically adapt to the volume changes of Zn anodes during repeated zinc plating/stripping processes through the reversible dissociation/reassociation of hierarchical hydrogen bonds (H-bonds) formed by the polar groups of urea and urethane moieties. Meanwhile, the coordination of Zn2+ with soft polypropylene glycol (PPG) segments contributes to fast ion transport. This hydrophobic elastomer can also effectively inhibit water-induced corrosion by shielding the active Zn metal from the aqueous electrolyte. Based on the above synergies, the surface-modified anode shows excellent cycling stability above 550 h at a high current density of 5 mA cm-2 and a capacity of 2.5 mAh cm-2. Moreover, the assembled Zn//MnO2 full cell also displayed an enhanced electrochemical performance. This work provides inspiration for the design of solid electrolyte interphase (SEI) layers in aqueous battery chemistry to accelerate the application of RAZBs.

Fatigue-Free and Skin-like Supramolecular Ion-Conductive Elastomeric Interphases for Stable Lithium Metal Batteries.

The heterogeneity and continuous cracking of the static solid electrolyte interphase (SEI) are one of the most critical barriers that largely limit the cycle life of lithium (Li) metal batteries. Herein, we report a fatigue-free dynamic supramolecular ion-conductive elastomeric interphase (DSIEI) for a highly efficient and dendrite-free lithium metal anode. The soft phase poly(propylene glycol) backbone with loosely Li+-O coordinating interaction was responsible for fast ion transport. Simultaneously, the supramolecular quadruple hydrogen bonds (H-bonds) in the hard phases endow the elastomeric interphase with mechanical enhancement, while gradient H-bonds can dissipate strain energy via the sequential bonding cleavage. Such a design affords superior mechanical robustness, high ionic conductivity, gradient energy dissipation, and high Li+ transference number. Besides, anion enrichment in DSIEI assists in situ construction of a lithium fluoride-rich inner layer upon cycling. The resultant biomimetic bilayer structure enables the symmetric cells with superior cyclability of over 600 h at a high current density of 10 mA cm-2. Moreover, the DSIEI allows stable operation of the full cells under constrained conditions of limited lithium excess, a high-loading LiNi0.8Co0.1Mn0.1O2 cathode, and a low negative/positive capacity (N/P) ratio. This work presents a powerful strategy for deigning artificial SEI and achieving high-energy-density Li metal batteries.

Colloid Electrolyte with Weakly Solvated Structure and Optimized Electrode/Electrolyte Interface for Zinc Metal Batteries.

Aqueous zinc batteries are considered as a viable candidate for cost-effective and environmentally sustainable energy storage technology but are severely hampered by the notorious dendrite growth and parasitic reactions at the zinc anode side. Herein, we propose a bifunctional colloidal electrolyte design that utilizes upconversion nanocrystals, i.e., NaErF4@NaYF4, as a solid additive to provide the sustained release of functional metal and fluoride ions, which can effectively improve the reversibility of the Zn anode to inhibit dendrite growth and hydrogen evolution through forming an electrostatic shielding layer and in situ constructing a ZnF2-enriched protective interface. Experimental characterization and molecular dynamics simulation jointly confirm that the NaErF4@NaYF4 additive could modify the Zn2+ solvation environment in the vicinity of the NaErF4@NaYF4 surface via the strong electrostatic coupling with Zn2+ ions. As a consequence, the modified electrolyte enables stable zinc plating/stripping over 2100 h at a current density of 3 mA cm-2 and a capacity of 1 mAh cm-2 in symmetric cells. The assembled Zn||MnO2 full cells with a modified electrolyte can operate stably for 1600 cycles at 2 A g-1. This work thereby has great potential for the exploration of multifunctional electrolyte additives toward long-lasting aqueous Zn metal batteries.

Green winner determination method based on environmental performance and minimum adjustment consensus in 4PL transportation service procurement.

Due to the intensified environmental protection consciousness of enterprises and consumers, the green winner determination (GWD) considering environmental performance becomes very important for the 4PL transportation service procurement. In this paper, a new GWD method is studied, which considers different types of attributes including those related to environmental performance and the consensus reaching process (CRP). To characterize multiple types of attributes, linguistic terms, interval numbers, and crisp numbers are combined. To achieve an acceptable consensus level among linguistic evaluations given by different experts, a minimum adjustment consensus model is constructed. And on this basis, an interactive CRP is proposed. Integrating the heterogeneous information addressing process and the CRP, a HC-VIKOR method is developed to promote the 4PL's operational efficiency and service quality. Further, a numerical example is designed to demonstrate the effectiveness of the proposed method. Sensitivity analysis reveals that both the acceptable consensus threshold and the weight of group utility have a significant influence on the winner determination result. Comparison analysis shows that the proposed method outperforms the existing methods. Our study not only extends the traditional winner determination but also provides decision support for the 4PL to provide transportation services efficiently.

The Institute of Medicine recommendation for gestational weight gain is probably not optimal among non-American pregnant women: a retrospective study from China.

PURPOSE: To investigate whether the Institute of Medicine (IOM) recommended gestational weight gain (GWG) range is optimal among Chinese singleton pregnant women. METHODS: For the purpose of a retrospective observational study, data on 8209 mature singleton deliveries in Shanghai from January 2014 to December 2016 were extracted from medical records in terms of clinical performance. All cases were categorized as undergainers, appropriate-gainers, and above-gainers according to IOM recommended gestational weight gain range after stratification of maternal BMI and proportions of three categories were calculated. Comparisons of maternal and neonatal outcome were conducted among three categories and the associations of those outcome including risks of low birth weight (LBW) and macrosomia (MAC) with GWG were estimated by logistic regression analysis. To examine the applicability of IOM recommendation for Chinese pregnant women, the accumulated risk of LBW and MAC was displayed by stacked column chart and comparison was made among GWG category. The joint predicted risk (JPR) curve of both LBW and MAC in relation to GWG (continuous measurement) was plotted to demonstrate the relation of lowest JPR corresponding GWG with IOM range. RESULTS: The IOM recommended weight gain was achieved only by 3502 (42.7%) pregnant women and 41.6% gained excessive weight during pregnancy, especially for the overweight and obese women, the proportions of above-gainers mounting to 65.7 and 75.9%, respectively. By multivariate analysis GWG significantly influenced the risk of MAC and caesarean section. Although the association between the risk of LBW and GWG was not significant, p value reached .051. The risk of delivering macrosomia and caesarean section doubled when GWG exceeded the IOM rang. Appropriate gainers did not always gain the lowest joint risk of low birth weight and macrosomia from stacked column chart and it is obvious that the GWG point according to the lowest JPR was always located left to the IOM recommended range for each BMI category from the JPR curve chart in relation to GWG. CONCLUSIONS: The IOM recommended GWG range is possibly too much for Chinese singleton pregnant population for each BMI category. It is necessary to build different gestational weight gain standards for specific ethnic population.

Mechanism design of incentive-based reverse auctions with loss-averse 3PLs under incomplete attributes.

As a supply chain solution integrator, fourth party logistics (4PL) has become an important focus for improving the operational efficiency of the logistics industry in recent days. This paper addresses the mechanism design problem of the 4PL for selecting a third party logistics (3PL) provider who involves loss-averse behavior to form a longer-term strategic partnership in multi-attribute reverse auctions. Due to fluctuating costs of energy or labor and unintentional delivery failures like traffic jam or technology malfunctions, we consider two incomplete attributes, namely cost uncertainty and delivery risk. Integrating the loss-averse behavior of 3PLs, based on the prospect theory, the bid decision model is constructed to obtain 3PLs' bidding strategies. The corresponding efficient and optimal scoring auctions that consist of cost-sharing contract and contingent penalty are developed to maximize the ex ante expected profit of the system or the 4PL depending on whether the 4PL is willing to cooperate or not. Theoretical analysis verified by numerical examples illustrates the advantage of the proposed mechanisms. Impacts of model parameters on the 4PL's decision are also investigated and managerial insights are presented.

Strain effects on the SERS enhancements for spherical silver nanoparticles.

We demonstrate in the present work through the utilization of classical Mie scattering theory in conjunction with a radiation damping and dynamic depolarization-corrected electrostatic approximation the significant effect that mechanical strain has on the optical properties of spherical silver nanoparticles. Through appropriate modifications of the bulk dielectric functions, we find that the application of tensile strain generates significant enhancements in the local electric field for the silver nanoparticles, leading to large SERS enhancements of more than 300% compared to bulk, unstrained nanoparticles when a 5% tensile strain is applied. While the strain-induced SERS enhancements are found to be strongest for nanoparticle diameters where radiation damping effects are minimized, we find that the surface plasmon resonance wavelengths are relatively unchanged by mechanical strain, and that the various measures of the far field optical efficiencies (absorption, scattering, extinction) can be enhanced by up to 150% through the application of tensile strain. The present findings indicate the opportunity to actively engineer and enhance the optical properties of silver nanoparticles through the application of mechanical deformation.