CeO2/Co heterostructure encapsulated in hollow necklace-like carbon fiber as an advanced host material for high-performance lithium-sulfur batteries.

The shuttle effect of lithium polysulfides (LiPSs) and the sluggish reaction kinetics of LiPSs conversion pose serious challenges to the commercial feasibility of lithium-sulfur (Li-S) batteries. To address these obstacles, herein, we construct CeO2/Co heterostructures in hollow necklace-like carbon fibers (CeO2/Co-CNFs) as the cathode host material for Li-S batteries. The specific surface area of fibers is significantly enhanced by using a template, thereby promoting the utilization efficiency of sulfur. Meanwhile, CeO2/Co-CNFs show strong conductivity, effective adsorption to LiPSs, and robust catalytic activity for LiPSs conversion. As a result, the Li-S battery with CeO2/Co-CNFs displays 961 mAh g-1 at 0.2 C, with an 86 % capacity retention rate after 100 cycles. At 2.0 C current density, the composite cathode maintains an initial discharge capacity of 782 mAh g-1, with a mere 0.044 % capacity loss per cycle. Furthermore, in situations with limited electrolytes, high sulfur loading, and high areal mass loading, the composite cathode can provide a high areal capacity of 6.2 mg cm-2 over 100 cycles. This work provides a useful approach for investigating high-performance Li-S battery cathodes.

Novel green/red oxyfluoride phosphors with excellent optical properties for near-UV excited white light emitting diode.

Novel eye-sensitive Ba3Nb2O2F12(H2O)2:Tb3+ green and Ba3Nb2O2F12(H2O)2:Mn4+ red oxyfluoride phosphors with extremely strong absorption in the UV region were designed and synthesized by simple co-precipitation strategy. Particularly, Tb3+ ions were doped in this matrix for the first time, which greatly improves their absorption efficiency in the near ultraviolet region (367 nm) and emits sharp green light (544 nm). In addition, the Ba3Nb2O2F12(H2O)2:Mn4+ red phosphors have strong zero phonon line (ZPL) emission at 625 nm, which is conducive to improving the sensitivity of human eye and color purity. Meanwhile, the optical properties of the red phosphor are significantly enhanced via doping K+ cations as charge compensators. Crystal field environment and nephelauxetic effect of the as-prepared phosphors before and after K+ cation doping were systematically analyzed. Moreover, these synthesized red/green phosphors have good thermal stability and moisture resistance. Remarkably, the as-prepared Ba3Nb2O2F12(H2O)2:5%Mn4+ or K0.9Ba2.1Nb2O2F12(H2O)2:5%Mn4+ red phosphors can be directly mixed with the as-synthesized Ba3Nb2O2F12(H2O)2:13%Tb3+ green phosphor coating on 365 nm near-ultraviolet LED chip to package WLED devices with excellent electroluminescence performance. These findings are conducive to opening an avenue for screening the unique structure of optical materials.

Highly Reversible Zn-Air Batteries Enabled by Tuned Valence Electron and Steric Hindrance on Atomic Fe-N4-C Sites.

The bifunctional oxygen electrocatalyst is the Achilles' heel of achieving robust reversible Zn-air batteries (ZABs). Herein, durable bifunctional oxygen electrocatalysis in alkaline media is realized on atomic Fe-N4-C sites reinforced by NixCo3-xO4 (NixCo3-xO4@Fe1/NC). Compared with that of pristine Fe1/NC, the stability of the oxygen evolution reaction (OER) is increased 10 times and the oxygen reduction reaction (ORR) performance is also improved. The steric hindrance alters the valence electron at the Fe-N4-C sites, resulting in a shorter Fe-N bond and enhanced stability of the Fe-N4-C sites. The corresponding solid-state ZABs exhibit an ultralong lifespan (>460 h at 5 mA cm-2) and high rate performance (from 2 to 50 mA cm-2). Furthermore, the structural evolution of NixCo3-xO4@Fe1/NC before and after the OER and ORR as well as charge-discharge cycling is explored. This work develops an efficient strategy for improving bifunctional oxygen electrocatalysis and possibly other processes.

Improving health and reducing health inequality: An innovation of digitalization?

RATIONALE: The association between digitalization and individual health has attracted increasing attention from both scholars and policymakers. Existing research, however, has not agreed on whether digitization can improve health or reduce health inequality. OBJECTIVE: The purpose of this study is to clarify whether and how the development of digitalization may be related to health and health disparities. METHODS: We rely on China Family Panel Studies (CFPS) surveys from 2012 to 2018 to obtain a sample of 82,471 observations to explore the impact of digitalization on self-rated health and health inequality and its transmission mechanisms. The hypotheses are tested by Ordinary Least Squares Modeling. RESULTS: As expected, digitalization is significantly and positively correlated with self-rated health. Furthermore, the development of digitalization has led to a notable decrease in health inequality. The influencing mechanisms of digitalization include income, healthcare consumption and health behaviors. Both dimensions of digitalization-internet development and digital finance-generate significant effects and the effects of internet development are greater. CONCLUSIONS: This study is the first to systematically investigate the impact of digitalization development on health and health inequality. Our findings provide evidence for the health promotion theory by clarifying the benefits of digitalization in improving residents' health and reducing health inequality. Therefore, utilizing the tools of digitalization efficiently could be a focus of policymakers aiming to accomplish the SDGs' health targets.

Built-in Electric Field Promotes Interfacial Adsorption and Activation of CO2 for C1 Products over a Wide Potential Window.

The unsatisfactory adsorption and activation of CO2 suppress electrochemical reduction over a wide potential window. Herein, the built-in electric field (BIEF) at the CeO2/In2O3 n-n heterostructure realizes the C1 (CO and HCOO-) selectivity over 90.0% in a broad range of potentials from -0.7 to -1.1 V with a maximum value of 98.7 ± 0.3% at -0.8 V. In addition, the C1 current density (-1.1 V) of the CeO2/In2O3 heterostructure with a BIEF is about 2.0- and 3.2-fold that of In2O3 and a physically mixed sample, respectively. The experimental and theoretical calculation results indicate that the introduction of CeO2 triggered the charge redistribution and formed the BIEF at the interfaces, which enhanced the interfacial adsorption and activation of CO2 at low overpotentials. Furthermore, the promoting effect was also extended to CeO2/In2S3. This work gives a deep understanding of BIEF engineering for highly efficient CO2 electroreduction over a wide potential window.

A ddPCR platform based on a microfluidic chip with a dual-function flow-focusing structure for sample-to-result DNA quantification analysis.

Droplet digital PCR (ddPCR) is a powerful method for absolute nucleic acid quantification with high precision and accuracy. However, complicated operational steps have hampered the use and diffusion of ddPCR. Therefore, an automated, easy-to-use, low-sample-consumption, and portable ddPCR platform is urgently needed. This paper proposes a microfluidic ddPCR platform based on a microfluidic chip that can realize the sample-to-result function by switching the rotary valve, achieving the dual function of the flow-focusing structure for droplet generation and readout. Sample, generation oil, and analysis oil were pre-added to the reservoirs. Droplets were generated due to focusing flow, and after passing through the integrated temporary storage bin in the rotary valve, the droplets and oil subsequently entered the collecting tube, improving the droplet-to-oil volume ratio for enhanced thermal cycle performance. Droplets with an average diameter of 107.44 µm and a CV of 2.38% were generated using our chip under the optimal pressures. High-performance thermal cycling was achieved through improvements of the droplet-to-oil volume ratio of the sample, the integrated heating lid, the pure copper heating base, and the temperature-controlling algorithm. Gradient quantification experiments were conducted for the HER2 and CEP17 genes extracted from breast cancer cells, yielding strong linear correlations with R2 values of 0.9996 for FAM and 0.9989 for CY5. Moreover, pronounced linearity was obtained between the detected concentrations of HER2 and CEP17, indicated by a slope of 1.0091 and an R2 of 0.9997, signifying consistent HER2 : CEP17 ratios across various sample dilutions. The outcomes of the quantitative analysis, encompassing the dynamic range and the consistency of the HER2 : CEP17 ratio using our ddPCR platform, meet the standards required for breast cancer assessment and therapy. Our ddPCR platform is automated, portable, and capable of stable droplet generation, high-efficiency amplification, realization of the sample-to-result function based on dual-function flow-focusing structure, and accuracy absolute quantification, underscoring its significant potential for ddPCR analysis in clinical diagnostics.

Dual-Confinement Effect of Nanocages@Nanotubes Suppresses Polysulfide Shuttle Effect for High-Performance Lithium-Sulfur Batteries.

The shuttle effect of lithium polysulfides (LiPSs) severely hinders the development and commercialization of lithium-sulfur batteries, and the design of high-conductive carbon fiber-host material has become a key solution to suppress the shuttle effect. In this work, a unique Co/CoN-carbon nanocages@TiO2-carbon nanotubes structure (NC@TiO2-CNTs) is constructed using an electrospinning and nitriding process. Lithium-sulfur batteries using NC@TiO2-CNTs as cathode host materials exhibit high sulfur utilization (1527 mAh g-1 at 0.2 C) and can still maintain a discharge capacity of 663 mAh g-1 at a high current density of 5 C, and the capacity loss is only 0.056% per cycle during 500 cycles at 1 C. It is worth noting that even under extreme conditions (sulfur-loading = 90%, surface-loading = 5.0 mg cm-2 (S), and E/S = 6.63 µL mg-1), the lithium-sulfur batteries can still provide a reversible capacity of 4 mAh cm-2. Throughdensity functional theory calculations, it has been found that the Co/CoN heterostructures can adsorb and catalyze LiPSs conversion effectively. Simultaneously, the TiO2 can adsorb LiPSs and transfer Li+ selectively, achieving dual confinement for the shuttle effect of LiPSs (nanocages and nanotubes). The new findings provide a new performance enhancement strategy for the commercialization of lithium-sulfur batteries.

Factors influencing the development of executive function in adolescents / 中国学校卫生

Abstract@#Executive function is an advanced cognitive process aimed at the flexible coordination, optimization, and control of the cognitive processes of task solving in order to accomplish a specific task, ensuring that the individual produces effective behaviors, including inhibitory control, working memory, and cognitive flexibility. Given the sensitivities and specificities that characterize an individual s physical and mental development during adolescence, this period is critical for the development of executive function in adolescents. In the paper, the influencing factors of adolescents executive function development are systematically described from three dimensions, namely, biology, environment and lifestyle; by analyzing the mechanisms and differences in the effects of different influencing factors, this editorial provides a scientific basis for adolescents executive function improvement and intervention.

Association between sedentary behaviors with cardiorespiratory fitness and executive function among adolescents / 中国学校卫生

Objective@#To explore the relationship between sedentary behavior with cardiorespiratory fitness and executive function in adolescents, and to provide some references for sedentary behavior prevention and executive function improvement.@*Methods@#From September to December 2022, a total of 5 018 adolescents aged 13 to 18 years were selected by stratified random sampling method in Shanghai, Suzhou, Taiyuan,Wuyuan, Xingyi, and Urumqi to conduct physical activity survey, as well as cardiorespiratory fitness and executive function assessment. Pearson s correlation was used to analyze the relationship between sedentary behavior, cardiorespiratory fitness and executive function. The mediation effect model was fitted by the bootstrap mediation procedure in the PROCESS (version 3.3 ) SPSS macro compiled by Haves, and the mediation effect of adolescents cardiorespiratory fitness in the relationship between static behavior and executive function was examined using model 4 in the PROCESS SPSS macro, where Boosrap method was used to compute the mediation effect of adolescents cardiorespiratory fitness. where the Boosrap method was used to calculate confidence intervals for the mediating effects.@*Results@#Adolescents daily sedentary time was positively correlated with both the refreshing function (1-back and 2-back) and the switch function reaction time ( r =0.05, 0.07, 0.05, P <0.01). Adolescent VO 2max was negatively correlated with both the refreshing function (1-back,2-back) and the switching function ( r =-0.09, -0.14 , -0.11, P <0.01). Adolescents daily sedentary time was negatively correlated with VO 2max ( r =-0.04, P <0.01); cardiorespiratory fitness mediated effect values between sedentary behavior and refreshing function (1-back and 2-back) and converted function were 0.20(95% CI =0.06-0.36), 0.43(95% CI =0.14-0.74) and 0.13 (95% CI =0.04-0.22), with mediating effect shares of 6.87%, 8.33% and 8.59%, respectively.@*Conclusion@#The duration of sedentary behavior in adolescents is related to executive function performance, and cardiorespiratory fitness may serve as a mediator to mediate the association between sedentary behavior and executive function in adolescents.

Intervention effects of moderate and high intensities of classroom physical activity on cardiorespiratory fitness and executive function among junior grade one students in Tibetan / 中国学校卫生

Objective@#To explore the intervention effect of different intensity of classroom physical exercise on cardiorespiratory fitness and executive function of Tibetan first grade students at high altitude, so as to provide reference for improving the level of cardiorespiratory fitness and executive function of Tibetan adolescents.@*Methods@#From September to December 2020, 184 Tibetan students from five first grade classes in a middle school in Lhasa, Tibet, were randomly assigned into a control group (81 students in two classes) and an intervention group (103 students in three classes). Both groups followed the same teaching programme, but the intervention group received 36 sessions of moderate to high intensity classroom physical activity, one session per day, Monday,Wednesday and Friday, for 12 weeks. Before and after the intervention, cardiorespiratory fitness and executive function were tested by 20m round trip running and Flanker s experimental paradigm, 2-back s experimental paradigm, and More odd shifting experimental paradigm for inhibitory control, refreshing memory, and switching flexibility, and the results were analysed by analysis of covariance (ANCOVA) to compare the results of the pre and post intervention periods.@*Results@#The maximum oxygen uptake (VO 2max ) of Tibetan first grade students in the intervention group increased by 2.25 mL/(kg〖WW）〗·〖WW(〗min) compared with the control group after the intervention ( t =-3.89, P <0.01); the response time of the inhibitory function was reduced by 4.40 ms, that of the refreshing function by 196.06 ms, and that of the switching function by 92.72 ms in the intervention group compared with the control group ( t =2.98, 4.82 ,3.21, P <0.05).@*Conclusion@#The 12 week moderate to high intensity classroom physical activity intervention has different degrees of improvement effects on cardiorespiratory fitness and executive function in Tibetan adolescents.

Relationship between cardiorespiratory fitness and executive function in adolescents / 中国学校卫生

Objective@#To explore the relationship between cardiorespiratory fitness and executive function in Chinese adolescents, so as to provide a reference for promoting the overall development of Chinese adolescents physical and mental health.@*Methods@#From September to December 2022, a total of 5 018 adolescents aged 13 to 18 years from Shanghai, Suzhou, Taiyuan, Wuyuan, Xingyi, and Urumqi were selected by stratified cluster sampling method to assess cardiorespiratory fitness and executive function. Pearson s correlation and linear hierarchical regression were performed to analyze the relationship between cardiorespiratory fitness and executive functions.@*Results@#Among the sample of adolescents, maximal oxygen consumption (VO 2max ) was negatively correlated with the refreshing(1-back, 2-back) and conversion executive function responses ( r=-0.07, -0.12, -0.12, P <0.01). Linear regression analysis showed that VO 2max was negatively correlated with the reaction times of the refreshing(1-back, 2-back) and conversion functions ( B=-2.99, -6.44, -1.69, P <0.01).@*Conclusions@#Higher cardiorespiratory fitness among adolescents is associated with better performance in executive function. Teenagers should strengthen high intensity cardiopulmonary endurance exercise to promote the improvement of executive function.

Executive functions of obese adolescents / 中国学校卫生

Objective@#To explore of executive function in obese adolescents, so as to provide a reference for executive function enhancement intervention in obese adolescents.@*Methods@#A convenience sample of 1 227 adolescents aged 13-18 years was selected from 2 secondary schools in Taiyuan City during March-April 2023. The Flanker task, N-back task and More odd shifting task was used to compare the different subfunctions of executive function (refreshing function, shifting function, inhibiting function) of 61 obese adolescents and 70 normal weight adolescents. Independent samples t-tests was used for between group comparisons and Cohen s d -tests was used to calculate between group differences in executive function between the two groups of adolescents.@*Results@#Compared with the group of normal weight, time responses of the inhibitory function [(29.73±19.55)ms], the refreshing function [1-back: (1 088.75±275.76)ms, 2-back:( 1 285.44± 355.16)ms] and the shifting function [(380.34±153.18) ms] in the obese group were significantly longer than those in the normal weight group [(14.86±20.27, 888.38±286.57, 1 126.20± 287.43 , 323.12±134.71) ms] ( t =4.26, 4.06, 1.92,2.26, P < 0.05 ); inhibitory function (0.91±0.09) and 1-back (0.73±0.24) were also significantly less correct than in the normal weight group (0.94±0.05, 0.83±0.21) ( t =-2.04, -2.04, P <0.05). Obese adolescents showed moderate adverse effect sizes in the inhibition function ( d =0.746,0.712) and the refresh function 1-back, and smaller adverse effect sizes in the refresh function 2-back and the conversion function( d =0.497,0.398).@*Conclusion@#Obese adolescents have significant executive function deficits, but the degree of adverse varies across sub-functions, with inhibitory function being the core deficit component of executive function in obese adolescents.

Deep-Orga: An improved deep learning-based lightweight model for intestinal organoid detection.

PROBLEM: Organoids are 3D cultures that are commonly used for biological and medical research in vitro due to their functional and structural similarity to source organs. The development of organoids can be assessed by morphological tests. However, manual analysis of organoid morphology requires intensive labor from professionals and is prone to observer discrepancies. AIM: Computer-assisted methods alleviate the pressure of manual labor, especially with the development of deep learning, the performance of morphological detection has been further improved. The aim of this paper is to automate the assessment of organoid morphology using deep learning techniques to reduce the labor pressure of professionals. METHODS: Based on the lightweight model YOLOX, a lightweight intestinal organoid detection model named Deep-Orga is proposed. First, the performance of the Deep-Orga model is compared with other classical models on the intestinal organoids dataset. Then, ablation experiments are used to validate the improvement of the model detection performance by the improved module. Finally, Deep-Orga is compared with other methods. RESULTS: Deep-Orga achieves optimal organoid detection with a partial increase in computational effort. Using Deep-Orga to replace the manual analysis process provides a new automated method for organoid morphology evaluation. CONCLUSION: Deep-Orga proposed in this paper is able to accurately assess organoid development, effectively relieving the labor pressure of professionals and avoiding the subjectivity of assessment. This paper demonstrates the potential application of deep learning in the field of organoid morphology analysis.

Long-cycle Zn-air batteries at high depth of discharge enabled by a robust Zn|electrolyte interface.

It is an urgent need to improve the depth of discharge (DOD) of Zn-air batteries (ZABs), considering that most reported ZABs with long cycle life are realized at low DOD (<1%). In this work, our solid-state ZABs achieved a long cycle life of more than 220 h at 3.2% DOD (the discharge capacity of 10 mA h cm-2 per cycle). Moreover, benefiting from excellent bifunctional oxygen electrocatalysts (Fe@BNC) and robust Zn|electrolyte interface, the ZABs displayed a long cycle life of 120 h even at high DOD of 23.4% and large discharge capacity of 72 mA h cm-2. Additionally, the impact of Zn|electrolyte interface on the cycle time at different DODs is analysed and discussed. The unstable interface exacerbated the dendrite growth and uneven deposition of Zn at high DOD, leading to the decay of the cycle life. The work gives insights into the mechanism of the effect of DOD on the cycle life of the batteries.

Optical enhancement of highly efficient organic-inorganic oxyfluoride red phosphors via the cation co-doping strategy.

Herein, a new organic cationic matrix [N(CH3)4]3MoO3F3 suitable for Mn4+ doping was constructed. Due to the large steric hindrance of N[CH3]4+ (TMA), charge compensation defects can be effectively prevented in the heterovalent Mn4+-doping process, and a high IQE (91.05%) was obtained. Through the cation co-doping strategy, Mg2+/Zn2+/Li+ cations were introduced into the Mo6+ cationic site, which improved the crystallinity of the matrix and reduced energy losses, so as to improve luminescence intensity, QE, thermal stability, water stability and other spectral properties. Meanwhile, [N(CH3)4]2TiF6:Mn4+ phosphors with the same TMA organic cation and equivalent Mn4+ doping were synthesized for comparison, and the effects of the Mg2+ cation co-doping strategy on the spectral properties of phosphors with different matrix types (fluoride/oxyfluoride) and substitution types (equivalent/non-equivalent) were analyzed. These findings provide the basis for the preparation of new luminescent materials. Furthermore, according to the optical properties exhibited by these phosphors, they are packaged into WLED devices with excellent photoelectric properties, which are suitable for indoor lighting and display fields.

Establishment and Validation of an Integrated Microfluidic Step Emulsification Chip Supporting Droplet Digital Nucleic Acid Analysis.

Uniform and stable droplet generation is critical for accurate and efficient digital nucleic acid analysis (dNAA). In this study, an integrated microfluidic step emulsification device with wide-range droplet generation capability, small device dimensions, convenient fabrication strategy, low contamination and high robustness was developed. A tree-shaped droplet generation nozzle distribution design was proposed to increase the uniformity of droplet generation by equating flow rates, and the flow field in the design was numerically simulated. Theoretical analysis and comparative experiments on droplet size were performed regarding the influences of nozzle dimensions and surface properties. With incubation and hydrophobic reagent treatment, droplets as small as 73.1 µm were generated with multiplex nozzles of 18 µm (h) × 80 µm (w). The droplets were then collected into a standard PCR tube and an on-chip monolayer droplet collection chamber, without manual transfer and sample contamination. The oil-to-sample volume ratio in the PCR tube was recorded during collection. In the end, the droplets generated and collected using the microfluidic device proved to be stable and uniform for nucleic acid amplification and detection. This study provides reliable characteristic information for the design and fabrication of a micro-droplet generation device, and represents a promising approach for the realization of a three-in-one dNAA device under a step emulsification method.

Insight on Atomically Dispersed Cu Catalysts for Electrochemical CO2 Reduction.

Electrochemical CO2 reduction (ECO2R) with renewable electricity is an advanced carbon conversion technology. At present, copper is the only metal to selectively convert CO2 into multicarbon (C2+) products. Among them, atomically dispersed (AD) Cu catalysts have received great attention due to the relatively single chemical environment, which are able to minimize the negative impact of morphology, valence state, and crystallographic properties, etc. on product selectivity. Furthermore, the completely exposed atomic Cu sites not only provide space and bonding electrons for the adsorption of reactants in favor of better catalytic activity but also provide an ideal platform for studying its reaction mechanism. This review summarizes the recent progress of AD Cu catalysts as a chemically tunable platform for ECO2R, including the atomic Cu sites dynamic evolution, the catalytic performance, and mechanism. Furthermore, the prospects and challenges of AD Cu catalysts for ECO2R are carefully discussed. We sincerely hope that this review can contribute to the rational design of AD Cu catalysts with enhanced performance for ECO2R.

miR-27a-5p inhibits acute rejection of liver transplantation in rats by inducing M2 polarization of Kupffer cells through the PI3K/Akt pathway.

Liver transplantation (LT), a major therapy for end-stage liver disease, is often associated with acute rejection (AR). MicroRNAs (miRNAs) have been implicated in AR-related gene regulation. In this experiment, the mechanism of miR-27a-5p in AR of LT was studied. Allotransplantation model (LEW-BN) and syngeneic transplantation model (LEW-LEW) of rat orthotopic liver transplantation (OLT) were established. miR-27a-5p was overexpressed in recipient rats 28 days before LT to detect its effects on LT pathology, liver function, and survival time. Kupffer cells (KCs) were isolated and treated with lipopolysaccharide (LPS) and miR-27a-5p overexpression. miR-27a-5p overexpression reduced lymphocyte numbers around portal areas and central veins after LT and mitigated degeneration of epithelial cells of the bile duct. Expression levels of IL-10 and TGF-ß1 were increased while IL-12 was decreased. Liver function damage was alleviated and the survival time of rats with LT was prolonged. miR-27a-5p induced M2 polarization of rats with AR after LT and LPS-treated KCs in vitro and promoted activation of the PI3K/Akt pathway in KCs. Inhibition of the PI3K/Akt pathway averted induction of miR-27a-5p on M2 polarization of KCs. Taken together, miR-27a-5p inhibited AR after LT in rats by inducing M2 polarization of KCs through the PI3K/Akt pathway.

Molecular property prediction by contrastive learning with attention-guided positive sample selection.

MOTIVATION: Predicting molecular properties is one of the fundamental problems in drug design and discovery. In recent years, self-supervised learning (SSL) has shown its promising performance in image recognition, natural language processing, and single-cell data analysis. Contrastive learning (CL) is a typical SSL method used to learn the features of data so that the trained model can more effectively distinguish the data. One important issue of CL is how to select positive samples for each training example, which will significantly impact the performance of CL. RESULTS: In this article, we propose a new method for molecular property prediction (MPP) by Contrastive Learning with Attention-guided Positive-sample Selection (CLAPS). First, we generate positive samples for each training example based on an attention-guided selection scheme. Second, we employ a Transformer encoder to extract latent feature vectors and compute the contrastive loss aiming to distinguish positive and negative sample pairs. Finally, we use the trained encoder for predicting molecular properties. Experiments on various benchmark datasets show that our approach outperforms the state-of-the-art (SOTA) methods in most cases. AVAILABILITY AND IMPLEMENTATION: The code is publicly available at https://github.com/wangjx22/CLAPS.

Enhanced lithium polysulfide adsorption on an iron-oxide-modified separator for Li-S batteries.

Lithium-sulfur (Li-S) batteries are candidates for next-generation energy storage systems because of their low cost, high theoretical specific capacity and safety. However, the serious lithium polysulfide (LiPS) shuttle effect leads to a loss of reactive active substances and reduction of coulombic efficiency. In the current work, iron oxide (IO-700)-prepared by calcining a mixture of carbon spheres and ferric nitrate under an air atmosphere at 700 °C-was designed as a separator modifier to effectively adsorb LiPSs and accelerate the kinetics of the transformation of the intermediates, thereby inhibiting the shuttle effect. Li-S batteries including IO-700 showed long-term stability for 1000 cycles at 1C, with a capacity decay rate per cycle of only 0.0487%. A theoretical calculation indicated that, due to strongly polar active sites, Fe2O3 adsorbed LiPSs effectively to suppress the shuttle effect. This work has highlighted the importance for Li-S batteries of strongly polar active sites for anchoring LiPSs to inhibit the shuttle effect.