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The formation of solid electrolyte interphase (SEI) and lithium ion intercalation are two crucial processes in lithium ion batteries. Given the complexity and challenges involved in investigating real batteries, a combination of model batteries comprising well-defined ultrathin graphite electrodes with surface-sensitive techniques can provide valuable information on these processes. Here, a comparative study of the performance of batteries using regular- and high-concentration electrolytes (RCE and HCE) is presented, aided by a myriad of correlative surface science techniques. It is found that the SEI formed in HCE possesses a thinner organic layer and more inorganic substances. Such an effective SEI protects the graphite electrode and facilitates the processes of Li+ intercalation/deintercalation, thereby improving the reversibility and cycling stability of the battery, superior to those with RCE. Moreover, the battery performance can be readily tuned by switching the electrolytes. The good cycling stability of the battery can still be maintained in RCE after the preformation of a robust SEI on the ultrathin graphite electrode in HCE. This work highlights the importance of electrolyte-modulated SEI formation to battery performance and provides powerful platforms to comprehensively study the SEI formation and ion intercalation processes. [ABSTRACT FROM AUTHOR]

With more accurate measurement method for gas samples, cross sections of the 14N(n,α0,1)11B reactions were measured at 24 energy points in the 4.5–11.5 MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University and the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE). The average neutron fluence (Φ) through the gas sample was obtained through the combination of a highly enriched 238U3O8 sample and the simulation based on SuperMC. The cross sections of the 14N(n,α0)11B reaction measured using the gas sample and the solid samples are in agreement with each other. R-matrix analysis was carried out for the n + 14N system using code RAC in the neutron energy region below 30 MeV. A possible valley structure in both the excitation functions of the 14N(n,α0,1)11B reactions in the 10–11 MeV neutron energy region was found for the first time. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the short‐term (1 week after completion of treatment) effect of office‐based vergence and anti‐suppression therapy (OBVAT) on the Office Control Score when compared to observation alone in children with small‐to‐moderate angle intermittent exotropia (IXT). Methods: In this single‐masked (examiner masked), two‐arm, single‐centre randomised clinical trial, 40 participants, 6 to <18 years of age with untreated IXT, were randomly assigned to OBVAT or observation alone. Participants assigned to therapy received 60 min of OBVAT with home reinforcement once per week for 16 weeks. Therapy included vergence, accommodation and anti‐suppression techniques. The primary outcome measure was the comparison of the distance Office Control Score between the two groups at the primary outcome visit (i.e., 17‐week follow‐up visit). Results: At the primary outcome visit, the OBVAT group (n = 20) had a significantly better distance Office Control Score (adjusted mean difference: −0.9; 95% CI: −0.2 to −1.5; p = 0.008; partial eta squared: 0.19) than the observation group (n = 16). Participants from the OBVAT group were more likely than those from the observation group to have ≥1 point of improvement at the 17‐week visit (OBVAT group: 75%; Observation group: 25%; p = 0.006). Conclusions: In this randomised clinical trial of participants aged 6 to <18 years with IXT, we found that the OBVAT group had a significantly better distance Office Control Score than the observation group at the 17‐week visit. This study provides the first data from a randomised clinical trial demonstrating the effectiveness of OBVAT for improving the control of IXT. Eye care practitioners should consider OBVAT as a viable, non‐surgical treatment option for IXT. A full‐scale randomised clinical trial investigating the long‐term effectiveness of OBVAT in treating IXT is warranted. [ABSTRACT FROM AUTHOR]

Achieving sustainable development is an issue of global concern. Accounting for the gross ecosystem product (GEP) value can specifically quantify the value of ecosystems for people, which is conducive to the formulation of sustainable management decisions. We have improved the GEP framework accounting method for the first time and evaluated the ecosystem service value of 36 cities in three provinces in the northeast (TPN) of China from 2000 to 2019, which provides decision‐making references for the sustainable development of TPN. The main accounting results and policy recommendations are as follows: (1) The ecological value of Northeast China is in an upward stage—GEP has increased from 3.1 trillion yuan in 2000 to 4.5 trillion yuan in 2019, with climate regulation and water conservation functions being the main driving factors for GEP. (2) Based on the dual analysis of GEP and gross domestic product (GDP), there is still high room for improvement in most cities in the TPN region. While ensuring the protection of ecosystem services, cities can convert ecological value into economic value through carbon trading, water rights trading, ecological compensation, and other methods based on ecological characteristics, which is conducive to the sustainable development of GDP and GEP in the TPN region in the future. (3) The cold and hot spot analysis of GEP also provides decision‐making basis for the planning of future ecosystem service protection areas in the TPN region. [ABSTRACT FROM AUTHOR]

Ensuring the structural safety of cemented gangue backfill (CGB) is crucial for safe mining operations. However, the complex mine water environment makes it susceptible to erosion by chemical ions, which have a significant time dependency. In this study, we evaluated the appearance, mass change, and unconfined compressive strength (UCS) of CGB during different chemical erosion times. We also determined the effect of chemical ion erosion time on the stress threshold for crack initiation and development in the specimens using acoustic emission (AE). Additionally, we examined the chemical erosion mechanism of CGB by scanning electron microscopy (SEM). Our results showed that as the erosion time increased, the CGB exhibited a decrease in brittleness and an increase in plasticity. During the first 60 days of CGB, the internal micropores and microfractures of the CGB were filled due to the hydration reaction and SO42− intrusion, resulting in increases in the UCS and the mass of the CGB. However, as the erosion time continued, H+ and SO42− intruded into the interior of the CGB, causing the erosion products of the CGB to expand in volume, leading to a decrease in the strength of the CGB. Our analysis of the stress thresholds for microcrack development and macrocracks initiation in the CGB showed an increase followed by a decline with time. After 60 days of immersion, the stress threshold for microcrack initiation and macrocrack extension increased by 20% and 6%, respectively. However, as the immersion time increased to 150 days, the stress threshold for microcrack initiation and macrocrack extension decreased by 56% and 16%, respectively. Therefore, the design of CGB safety needs to consider the long-term effects of chemical attacks on CGB. [ABSTRACT FROM AUTHOR]