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For three-phase alternating current (ac) contactors, the degradation of switching performance is affected by the accumulated arc erosion on contacts seriously. The direct consequence is the asynchronous contact breaking behavior and further disconnection failure. In this article, we explicitly recorded the typical contact voltage, contact current, and coil current waveforms of the contactor during ac-1 electrical endurance tests. Through the analysis of the waveforms, the asynchronous bridge breaking phenomenon within the three-phase ac contactor is discovered. Furthermore, by examining variations in bridge breaking time difference and opening time difference among phases with operation cycles, the correlation between asynchronous bridge breaking behavior and associated unbalanced arc erosion is analyzed explicitly. Finally, the failure mechanisms for the three-phase ac contactor are proposed based on the asynchronous break phenomenon of the contact bridge and the asynchronous separation phenomenon of the three phases.

Realizing room-temperature, efficient, and reversible fluoride-ion redox is critical to commercializing the fluoride-ion battery, a promising post-lithium-ion battery technology. However, this is challenging due to the absence of usable electrolytes, which usually suffer from insufficient ionic conductivity and poor (electro)chemical stability. Herein we report a water-in-salt (WIS) electrolyte based on the tetramethylammonium fluoride salt, an organic salt consisting of hydrophobic cations and hydrophilic anions. The new WIS electrolyte exhibits an electrochemical stability window of 2.47 V (2.08–4.55 V vs Li+/Li) with a room-temperature ionic conductivity of 30.6 mS/cm and a fluoride-ion transference number of 0.479, enabling reversible (de)fluoridation redox of lead and copper fluoride electrodes. The relationship between the salt property, the solvation structure, and the ionic transport behavior is jointly revealed by computational simulations and spectroscopic analysis.

AbstractBackgroundInflammation plays a pivotal role in the pathogenesis of heart failure (HF). This study was aimed to the potential association between complete blood cell count (CBC)-derived inflammatory biomarkers and HF.MethodsData from the National Health and Nutrition Examination Survey (NHANES) 2009-2018 were utilised. We evaluated the associations between HF and five systemic inflammation markers derived from CBC: systemic immune-inflammation index (SII), systemic inflammatory response index (SIRI), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR). Demographic characteristics, physical examinations, and laboratory data were systematically collected for comparative analysis between HF and non-HF individuals. Fitted smoothing curves and threshold effect analysis delineated the relationship. In addition, Spearman correlation and subgroup analyses were further conducted.ResultsA total of 26,021 participants were categorised into HF (n = 858) and non-HF (n = 25,163) groups. After adjusting for confounding variables, SIRI, NLR, and MLR had significant positive correlations with the risk of HF. Participants in the highest quarter groups of SIRI, NLR, and MLR showed a increased risk of developing HF compared to those in the lowest quarter group. Furthermore, subgroup and sensitivity analyses indicated that SIRI, NLR, and MLR had a stronger correlation to HF (all p < 0.05). Smoothing curve fitting highlighted a nonlinear relationship between CBC-derived inflammatory biomarkers and HF.ConclusionsOur results illustrated a significant association between elevated levels of SIRI, NLR, and MLR and an increased risk of HF. SIRI, NLR, and MLR could potentially serve as systemic inflammation hazard markers for HF.

Solid-state lithium-metal (Li0) batteries are gaining traction for electric vehicle applications because they replace flammable liquid electrolytes with a safer, solid-form electrolyte that also offers higher energy density and better resistance against Li dendrite formation. Solid polymer electrolytes (SPEs) are highly promising candidates because of their tuneable mechanical properties and easy manufacturability; however, their electrochemical instability against lithium-metal (Li0), mediocre conductivity and poorly understood Li0/SPE interphases have prevented extensive application in real batteries. In particular, the origin of the low Coulombic efficiency (CE) associated with SPEs remains elusive, as the debate continues as to whether it originates from unfavoured interfacial reactions or lithium dendritic growth and dead lithium formation. In this work, we use state-of-the-art cryo-EM imaging and spectroscopic techniques to characterize the structure and chemistry of the interface between Li0and a polyacrylate-based SPE. Contradicting the conventional knowledge, we find that no protective interphase forms, owing to the sustained reactions between deposited Li dendrites and polyacrylic backbones and succinonitrile plasticizer. Due to the reaction-induced volume change, large amounts of cracks form inside the Li dendrites with a stress–corrosion–cracking behaviour, indicating that Li0cannot be passivated in this SPE system. On the basis of this observation, we then introduce additive engineering, leveraging from knowledge of liquid electrolytes, and demonstrate that the Li0surface can be effectively protected against corrosion using fluoroethylene carbonate, leading to densely packed Li0domes with conformal and stable solid–electrolyte interphase films. Owing to the high room-temperature ionic conductivity of 1.01 mS cm−1, the high transference number of 0.57 and the stabilized lithium–electrolyte interface, this improved SPE delivers an excellent lithium plating/stripping CE of 99% and 1,800 hours of stable cycling in Li||Li symmetric cells (0.2 mA cm−2, 1 mAh cm−2). This improved cathodic stability, along with the high anodic stability, enables a record high cycle life of >2,000 cycles for Li||LiFePO4and >400 cycles for Li||LiCoO2full cells.

Solid polymer electrolytes (SPEs) have the potential to enhance the safety and energy density of lithium batteries. However, poor interfacial contact between the lithium metal anode and SPE leads to high interfacial resistance and low specific capacity of the battery. In this work, we present a novel strategy to improve this solid–solid interface problem and maintain good interfacial contact during battery cycling by introducing an adaptive buffer layer (ABL) between the Li metal anode and SPE. The ABL consists of low molecular-weight polypropylene carbonate , poly(ethylene oxide) (PEO), and lithium salt. Rheological experiments indicate that ABL is viscoelastic and that it flows with a higher viscosity compared to PEO-only SPE. ABL also has higher ionic conductivity than PEO-only SPE. In the presence of ABL, the interface resistance of the Li/ABL/SPE/LiFePO4battery only increased 20% after 150 cycles, whereas that of the battery without ABL increased by 117%. In addition, because ABL makes a good solid–solid interface contact between the Li metal anode and SPE, the battery with ABL delivered an initial discharge specific capacity of >110 mA·h/g, which is nearly twice that of the battery without ABL, which is 60 mA·h/g. Moreover, ABL is able to maintain electrode–electrolyte interfacial contact during battery cycling, which stabilizes the battery Coulombic efficiency.

As a critical component of alkaline fuel cells, anion exchange membranes determine the energy efficiency, output power density and the long term stability. Recently, the anion exchange membranes with gemini-cation side chains exhibit superior ion conductivity due to their good nanophase separation. However, the costly and complicated synthesis limits their scaling up and commercialization. To address this problem, a convenient synthetic procedure under mild conditions is well developed. A tertiary amine precursor is introduced onto the polymer by the nucleophilic substitution reaction to avoid the conventional chloro/bromo-methylation. Followed by a simple Menshutkin reaction with 6-bromo-N,N,N-trimethylhexan-1-aminium bromide, the polymer electrolytes are obtained in a high yield. The resulting anion exchange membranes with high conductivity, good fuel cell performance and restricted swelling suggest the potential for the application in fuel cell devices. 作为碱性燃料电池的关键组分, 阴离子交换膜决定了其能量转化效率, 输出功率密度及长期稳定性. 最近, 带有双离子侧链的阴离子交换膜, 因其良好的微相分离能力, 表现出了优异的离子电导率. 然而, 昂贵且复杂的合成方法限制了其商业化应用. 为了解决这一问题, 本文开发了一种简单、温和的合成方法. 首先通过亲核取代反应将叔胺前驱体引入到聚合物主链上, 避免了常用的氯/溴甲基化反应. 随后与溴己基-N,N,N-三甲基铵进行简单的门秀金反应, 以高产率获得目标聚合物电解质. 所得到的阴离子交换膜表现出高的离子电导率, 良好的燃料电池性能以及有限的溶胀, 表明所提出的策略在燃料电池中具有应用前景.

Solid polymer electrolytes (SPEs) offer potential advantages over liquid electrolytes, including flexibility, safety, and processability. However, they suffer from low room-temperature ionic conductivity. Recently, it has been reported a poly(ethyl acrylate) based (polyEA) SPE, by incorporating 50 wt% of succinonitrile (SN) solid plasticizer, 30 wt% of lithium salt and 5 wt% of fluoroethylene carbonate additive, which achieves a high room-temperature ionic conductivity of 1.01 × 10−3 S cm−1(Nat. Nanotechnol, 2022, 17, 768-776). This novel SPE exhibits stability against Li0and anodic stability up to 4.9 V vs Li+/Li. However, the specific mechanism responsible for its high ionic conductivity remains elusive. In this work, by adjusting the weight ratio of SN in the SPE, a transition from Vogel-Fulcher-Tammann to Arrhenius ion-conducting behavior is observed. It is demonstrated that the addition of SN leads to the gradual decoupling of Li-ion from the polymer backbone and its coordination with SN, as revealed by 6Li solid-state nuclear magnetic resonance spectroscopy. As a result, Li-ion migration primarily occurs through SN rather than the segmental motion of the polymer backbone. Performances of the SPE in Cu||Li, Li||Li and a LiFePO4||Li pouch cells are shown to demonstrate the commercial viability of this SPE in Li0-anode solid-state batteries.

Lipid transfer inhibitor protein (LTIP) is a physiologic regulator of cholesteryl ester transfer protein (CETP) function. We previously reported that LTIP activity is localized to LDL, consistent with its greater inhibitory activity on this lipoprotein. With a recently described immunoassay for LTIP, we investigated whether LTIP mass is similarly distributed. Plasma fractionated by gel filtration chromatography revealed two LTIP protein peaks, one coeluting with LDL, and another of ∼470 kDa. The 470 kDa LTIP complex had a density of 1.134 g/ml, indicating ∼50% lipid content, and contained apolipoprotein A-I. By mass spectrometry, partially purified 470 kDa LTIP also contains apolipoproteins C-II, D, E, J, and paraoxonase 1. Unlike LDL-associated LTIP, the 470 kDa LTIP complex does not inhibit CETP activity. In normolipidemic subjects, ∼25% of LTIP is in the LDL-associated, active form. In hypercholesterolemia,this increases to 50%, suggesting that lipoprotein composition may influence the status of LTIP activity. Incubation (37°C) of normolipidemic plasma increased active, LDL-associated LTIP up to 3-fold at the expense of the inactive pool. Paraoxon inhibited this shift by 50%. Overall, these studies show that LTIP activity is controlled by its reversible incorporation into an inactive complex. This may provide for short-term fine-tuning of lipoprotein remodeling mediated by CETP.

Lipid transfer inhibitor protein (LTIP) is a physiologic regulator of cholesteryl ester transfer protein (CETP) function. We previously reported that LTIP activity is localized to LDL, consistent with its greater inhibitory activity on this lipoprotein. With a recently described immunoassay for LTIP, we investigated whether LTIP mass is similarly distributed. Plasma fractionated by gel filtration chromatography revealed two LTIP protein peaks, one coeluting with LDL, and another of ∼470 kDa. The 470 kDa LTIP complex had a density of 1.134 g/ml, indicating ∼50% lipid content, and contained apolipoprotein A-I. By mass spectrometry, partially purified 470 kDa LTIP also contains apolipoproteins C-II, D, E, J, and paraoxonase 1. Unlike LDL-associated LTIP, the 470 kDa LTIP complex does not inhibit CETP activity. In normolipidemic subjects, ∼25% of LTIP is in the LDL-associated, active form. In hypercholesterolemia,this increases to 50%, suggesting that lipoprotein composition may influence the status of LTIP activity. Incubation (37°C) of normolipidemic plasma increased active, LDL-associated LTIP up to 3-fold at the expense of the inactive pool. Paraoxon inhibited this shift by 50%. Overall, these studies show that LTIP activity is controlled by its reversible incorporation into an inactive complex. This may provide for short-term fine-tuning of lipoprotein remodeling mediated by CETP.

The rechargeability of aqueous zinc metal batteries is plagued by parasitic reactions of the zinc metal anode and detrimental morphologies such as dendritic or dead zinc. To improve the zinc metal reversibility, hereby we report a new solution structure of aqueous electrolyte with hydroxyl-ion scavengers and hydrophobicity localized in solvent clusters. We show that although hydrophobicity sounds counterintuitive for an aqueous system, hydrophilic pockets may be encapsulated inside a hydrophobic outer layer, and a hydrophobic anode–electrolyte interface can be generated through the addition of a cation-philic, strongly anion-phobic, and OH–-reactive diluent. The localized hydrophobicity enables less active water and less absorbed water on the Zn anode surface, which suppresses the parasitic water reduction; while the hydroxyl-ion-scavenging functionality further minimizes undesired passivation layer formation, thus leading to superior reversibility (an average Zn plating/stripping efficiency of 99.72% for 1000 cycles) and lifetime (80.6% capacity retention after 5000 cycles) of zinc batteries.