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Photo-assisted Zn-air batteries can accelerate the kinetics of oxygen reduction and oxygen evolution reactions (ORR/OER); however, challenges such as rapid charge carrier recombination and continuous electrolyte evaporation remain. Herein, for the first time, piezoelectric catalysis is introduced in a photo-assisted Zn-air battery to improve carrier separation capability and accelerate the ORR/OER kinetics of the photoelectric cathode. The designed microhelical catalyst exploits simple harmonic vibrations to regenerate the built-in electric field continuously. Specifically, in the presence of the low-frequency kinetic energy that occurs during water flow, the piezoelectric-photocoupling catalyst of poly(vinylidene fluoride-co-trifluoroethylene)@ferric oxide(Fe@P(V-T)) is periodically deformed, generating a constant reconfiguration of the built-in electric field that separates photogenerated electrons and holes continuously. Further, on exposure to microvibrations, the gap between the charge and discharge potentials of the Fe@P(V-T)-based photo-assisted Zn-air battery is reduced by 1.7 times compared to that without piezoelectric assistance, indicating that piezoelectric catalysis is highly effective for enhancing photocatalytic efficiency. This study provides a thorough understanding of coupling piezoelectric polarization and photo-assisted strategy in the field of energy storage and opens a fresh perspective for the investigation of multi-field coupling-assisted Zn-air batteries.
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Uncontrollable interfacial side reactions generated from common aqueous electrolytes, just like the hydrogen evolution reaction (HER) and dendrite growth, have severely prevented the practical application of zinc-ion batteries (ZIBs). Solid-state ZIBs are considered to be an efficient strategy by adopting high-quality solid-state electrolytes (SSEs). Here, by confining deep eutectic electrolyte (DEE) into the nanochannels of metal-organic framework (MOF)-PCN-222, a stable DEE@PCN-222 SSE with internal Zn2+ transport channels was obtained. A distinctive ion-transport network composed of DEE and PCN-222 in the interior of DEE@PCN-222 realizes the efficient Zn2+ conduction, contributing to high ionic conductivity of 3.13×10-4â S cm-1 at room temperature, low activation energy of 0.12â eV, and a high Zn2+ transference number of 0.74. Furthermore, experimental and theoretical investigations demonstrate that DEE@PCN-222 with its unique channel structure could homogeneously regulate the Zn2+ distribution and effectively alleviate the side reactions. Highly reversible Zn plating/stripping performance of 2476â h can be realized by the SSE. The solid-state ZIBs show a specific capacity of 306â mAh g-1 and display cycling stability of 517â cycles. This unique design concept provides a new perspective in realizing the high-safety and high-performance ZIBs.
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The lack of stable solid-state electrolytes (SSEs) with high-ionic conductivity and rational design of electrode/electrolyte interfaces remains challenging for solid-state lithium batteries. Here, for the first time, a high-performance solid-state lithium-oxygen battery is developed based on the Li-ion-conducted hydrogen-bonded organic framework (LHOF) electrolyte and the core-shell HOF-DAT@CNT cathode with a few layers of HOF-DAT on surface of carbon nanotubes. Benefiting from the abundant dynamic hydrogen bonding network in LHOF-DAT SSEs, fast Li+ ion transport (2.2 × 10-4 S cm-1), a high Li+ transfer number (0.88), and a wide electrochemical window of 5.05 V are achieved. Symmetric batteries constructed with LHOF-DAT SSEs exhibit a stably cycled duration of over 1400 h, which mainly stems from the jumping sites that promote a uniformly high rate of Li+ flux and the hydrogen-bonding network structure that can relieve the structural changes during Li+ transport. LHOF-DAT SSEs-based Li-O2 batteries exhibit high specific capacity (10335 mAh g-1), and stable cycling life up to 150 cycles. Moreover, the solid-state lithium metal battery with LHOF-DAT SSEs endow good rate capability (128.8 mAh g-1 at 1 C), long-term discharge/charge stability (210 cycles). The design of LHOF-DAT SSEs opens an avenue for the development of novel SSEs-based solid-state lithium batteries.
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Multifunctional fibers represent a cornerstone of human civilization, playing a pivotal role in numerous aspects of societal development. Natural biomaterials, in contrast to synthetic alternatives, offer environmental sustainability, biocompatibility, and biodegradability. Among these biomaterials, natural silk is favored in biomedical applications and smart fiber technology due to its accessibility, superior mechanical properties, diverse functional groups, controllable structure, and exceptional biocompatibility. This review delves into the intricate structure and properties of natural silk fibers and their extensive applications in biomedicine and smart fiber technology. It highlights the critical significance of silk fibers in the development of multifunctional materials, emphasizing their mechanical strength, biocompatibility, and biodegradability. A detailed analysis of the hierarchical structure of silk fibers elucidates how these structural features contribute to their unique properties. The review also encompasses the biomedical applications of silk fibers, including surgical sutures, tissue engineering, and drug delivery systems, along with recent advancements in smart fiber applications such as sensing, optical technologies, and energy storage. The enhancement of functional properties of silk fibers through chemical or physical modifications is discussed, suggesting broader high-end applications. Additionally, the review addresses current challenges and future directions in the application of silk fibers in biomedicine and smart fiber technologies, underscoring silk's potential in driving contemporary technological innovations. The versatility and sustainability of silk fibers position them as pivotal elements in contemporary materials science and technology, fostering the development of next-generation smart materials.
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Materiais Biocompatíveis , Seda , Têxteis , Seda/química , Materiais Biocompatíveis/química , Humanos , Engenharia Tecidual , Animais , Sistemas de Liberação de MedicamentosRESUMO
Solid-state lithium-oxygen (Li-O2) batteries have been widely recognized as one of the candidates for the next-generation of energy storage batteries. However, the development of solid-state Li-O2 batteries has been hindered by the lack of solid-state electrolyte (SSE) with high ionic conductivity at room temperature, high Li+ transference number, and the high stability to air. Herein, the organic molecular porous solid cucurbit[7]uril (CB[7]) with one-dimensional (1D) ion migration channels is developed as the SSE for solid-state Li-O2 batteries. Taking advantage of the 1D ion migration channel for Li+ conduction, CB[7] SSE achieves high ionic conductivity (2.45 × 10-4 S cm-1 at 25 °C). Moreover, the noncovalent interactions facilitated the immobilization of anions, realizing a high Li+ transference number (tLi + = 0.81) and Li+ uniform distribution. The CB[7] SSE also shows a wide electrochemical stability window of 0-4.65 V and high thermal stability and chemical stability, as well as realizes stable Li+ plating/stripping (more than 1000 h at 0.3 mA cm-2). As a result, the CB[7] SSE endows solid-state Li-O2 batteries with superior rate capability and long-term discharge/charge stability (up to 500 h). This design strategy of CB[7] SSE paves the way for stable and efficient solid-state Li-O2 batteries toward practical applications.
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BACKGROUND: The abnormality of chromosomal karyotype is one factor causing poor prognosis of lymphoma. In the analysis of abnormal karyotype of lymphoma patients, three smallest overlap regions were found, in which MYCT1 was located. MYCT1 is the first tumor suppressor gene cloned by our research team, but its studies relating to the occurrence and development of lymphoma have not been reported. METHODS: R banding analyses were employed to screen the abnormality of chromosomal karyotype in clinical specimen and MYCT1 over-expression cell lines. FISH was to monitor MYCT1 copy number aberration. RT-PCR and Western blot were to detect the mRNA and protein levels of the MYCT1 and RUNX1 genes, respectively. The MYCT1 and RUNX1 protein levels in clinical specimen were evaluated by immunohistochemical DAB staining. The interaction between MYCT1 and MAX proteins was identified via Co-IP and IF. The binding of MAX on the promoter of the RUNX1 gene was detected by ChIP and Dual-luciferase reporter assay, respectively. Flow cytometry and CCK-8 assay were to explore the effects of MYCT1 and RUNX1 on the cell cycle and proliferation, respectively. RESULTS: MYCT1 was located in one of three smallest overlap regions of diffuse large B-cell lymphoma, it altered chromosomal instability of diffuse large B-cell lymphoma cells. MYCT1 negatively correlated with RUNX1 in lymphoma tissues of the patients. MAX directly promoted the RUNX1 gene transcription by binding to its promoter region. MYCT1 may represses RUNX1 transcription by binding MAX in diffuse large B-cell lymphoma cells. MYCT1 binding to MAX probably suppressed RUNX1 transcription, leading to the inhibition of proliferation and cell cycle of the diffuse large B-cell lymphoma cells. CONCLUSION: This study finds that there is a MYCT1-MAX-RUNX1 signaling pathway in diffuse large B-cell lymphoma. And the study provides clues and basis for the in-depth studies of MYCT1 in the diagnosis, treatment and prognosis of lymphoma.
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Subunidade alfa 2 de Fator de Ligação ao Core , Linfoma Difuso de Grandes Células B , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Regiões Promotoras Genéticas , Linfoma Difuso de Grandes Células B/genética , Hematopoese , Linhagem Celular Tumoral , Proteínas Nucleares/metabolismoRESUMO
Li-N2 batteries have received widespread attention for their potential to integrate N2 fixation, energy storage, and conversion. However, because of the low activity and poor stability of cathode catalysts, the electrochemical performance of Li-N2 batteries is suboptimal, and their electrochemical reversibility has rarely been proven. In this study, a novel bifunctional photo-assisted Li-N2 battery system was established by employing a plasmonic Au nanoparticles (NPs)-modified defective carbon nitride (Au-Nv -C3 N4 ) photocathode. The Au-Nv -C3 N4 exhibits strong light-harvesting, N2 adsorption, and N2 activation abilities, and the photogenerated electrons and hot electrons are remarkably beneficial for accelerating the discharge and charge reaction kinetics. These advantages enable the photo-assisted Li-N2 battery to achieve a low overpotential of 1.32â V, which is the lowest overpotential reported to date, as well as superior rate capability and prolonged cycle stability (≈500â h). Remarkably, a combination of theoretical and experimental results demonstrates the high reversibility of the photo-assisted Li-N2 battery. The proposed novel strategy for developing efficient cathode catalysts and fabricating photo-assisted battery systems breaks through the overpotential bottleneck of Li-N2 batteries, providing important insights into the mechanism underlying N2 fixation and storage.
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Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.
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Solid-state lithium (Li) batteries promise both high energy density and safety while existing solid-state electrolytes (SSEs) fail to satisfy the rigorous requirements of battery operations. Herein, novel polyoxometalate SSEs, Li3 PW12 O40 and Li3 PMo12 O40 , are synthesized, which exhibit excellent interfacial compatibility with electrodes and chemical stability, overcoming the limitations of conventional SSEs. A high ionic conductivity of 0.89â mS cm-1 and a low activation energy of 0.23â eV are obtained due to the optimized three-dimensional Li+ migration network of Li3 PW12 O40 . Li3 PW12 O40 exhibits a wide window of electrochemical stability that can both accommodate the Li anode and high-voltage cathodes. As a result, all-solid-state Li metal batteries fabricated with Li/Li3 PW12 O40 /LiNi0.5 Co0.2 Mn0.3 O2 display a stable cycling up to 100 cycles with a cutoff voltage of 4.35â V and an areal capacity of more than 4â mAh cm-2 , as well as a cost-competitive SSEs price of $5.68â kg-1 . Moreover, Li3 PMo12 O40 homologous to Li3 PW12 O40 was obtained via isomorphous substitution, which formed a low-resistance interface with Li3 PW12 O40 . Applications of Li3 PW12 O40 and Li3 PMo12 O40 in Li-air batteries further demonstrate that long cycle life (650 cycles) can be achieved. This strategy provides a facile, low-cost strategy to construct efficient and scalable solid polyoxometalate electrolytes for high-energy solid-state Li metal batteries.
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Applying solar energy into energy storage battery systems is challenging in achieving green and sustainable development, however, the efficient progress of photo-assisted metal-air batteries is restricted by the rapid recombination of photogenerated electrons and holes upon the photocathode. Herein, a 1D-ordered MoS2 nanotube (MoS2-ONT) with confined mass transfer can be used to extend the lifetime of photogenerated carriers, which is capable of overcoming the challenge of rapid recombination of electron and holes. The tubular confined space cannot only promote the orderly separation and migration of charge carriers but also realize the accumulation of charge and the rapid activation of oxygen molecules. The concave surface of MoS2-ONT can improve the carrier separation ability and prolong the carrier lifetime. Meanwhile, the ordered tubular confined space can effectively realize the rapid transfer of charge, ion, and oxygen. Under light irradiation, a fast oxygen reduction reaction kinetics of 70 mW cm-2 for photo-assisted Zn-air battery is achieved, which is the highest value reported for photo-assisted Zn-air batteries. Significantly, the photo-assisted Li-O2 battery based on MoS2-ONT also shows superior rate capability and other exciting battery performance. This work shows the universality of the confined carrier separation strategy in photo-assisted metal-air batteries.
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To investigate the impacts of abrupt warming on tree growth, we collected tree ring cores from larch (Larix principis-rupprechtii) in three different sites, including Saihanba National Nature Reserve, Pangquangou National Nature Reserve, and Fengning Qiansongba National Forest Park. Based on the tree ring method, Mann-Kendall test was used to examine the occurrence time of temperature rise mutation. We further analyzed the radial growth law of larch before and after the temperature mutation and its correlation with the monthly climate data. The results showed that the sudden temperature rise occurred in the Saihanba area in 1987, the Fengning area in 1989, and the Pangquangou area 1994. Before the sudden warming, there was no significant trend for the radial growth in all the three regions. After the sudden warming, however, it decreased significantly (with a decrease rate of 0.08·10 a-1) in Saihanba area. The radial growth of larch increased significantly in Pangquangou area (with an increase rate of 0.10·10 a-1), while no significant change was observed in the Fengning area. Before the sudden warming, there was a significant positive correlation between the radial growth of larch in the Saihanba area and the highest temperature in May and June. After the sudden warming, there was a significant positive correlation with precipita-tion in July, and a highly significant positive correlation with the standardized precipitation evapotranspiration index(SPEI) from September of the previous year to July. Prior to the sudden warming, there was no significant relationship between the radial growth of larch in the Pangquangou area and monthly climate factors. However, after the sudden warming, a significant positive correlation was found with the lowest temperature in September of the pre-vious year. Before the sudden warming, the radial growth of larch in Fengning area was significantly negatively correlated with the lowest average temperature in July. After the sudden warming, it showed a significant negative correlation with the average and highest temperatures in June. Accordingly, the radial growth of larch in the Saihanba area experienced drought stress following a sudden temperature change. If temperature continues to rise in the future, larch in the Fengning area would also face drought stress. Conversely, warming conditions would be beneficial for the radial growth of larch in the Pangquangou area.
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Larix , Larix/fisiologia , Clima , Florestas , Árvores , Temperatura , ChinaRESUMO
Rechargeable lithium-oxygen (Li-O2 ) batteries with high theoretical energy density are considered as promising candidates for portable electronic devices and electric vehicles, whereas their commercial application is hindered due to poor cyclic stability caused by the sluggish kinetics and cathode passivation. Herein, the intrinsic stress originated from the growth and decomposition of the discharge product (lithium peroxide, Li2 O2 ) is employed as a microscopic pressure resource to induce the built-in electric field, further improving the reaction kinetics and interfacial Lithium ion (Li+ ) transport during cycling. Piezopotential caused by the intrinsic stress-strain of solid Li2 O2 is capable of providing the driving force for the separation and transport of carriers, enhancing the Li+ transfer, and thus improving the redox reaction kinetics of Li-O2 batteries. Combined with a variety of in situ characterizations, the catalytic mechanism of barium titanate (BTO), a typical piezoelectric material, was systematically investigated, and the effect of stress-strain transformation on the electrochemical reaction kinetics and Li+ interface transport for the Li-O2 batteries is clearly established. The findings provide deep insight into the surface coupling strategy between intrinsic stress and electric fields to regulate the electrochemical reaction kinetics behavior and enhance the interfacial Li+ transport for battery system.
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Solid-state electrolytes (SSEs) with high ionic conductivity and superior stability are considered to be a key technology for the safe operation of solid-state lithium batteries. However, current SSEs are incapable of meeting the requirements for practical solid-state lithium batteries. Here we report a general strategy for achieving high-performance SSEs by engineering polymers of intrinsic microporosity (PIMs). Taking advantage of the interconnected ion pathways generated from the ionizable groups, high ionic conductivity (1.06×10-3 â S cm-1 at 25 °C) is achieved for the PIMs-based SSEs. The mechanically strong (50.0â MPa) and non-flammable SSEs combine the two superiorities of outstanding Li+ conductivity and electrochemical stability, which can restrain the dendrite growth and prevent Li symmetric batteries from short-circuiting even after more than 2200â h cycling. Benefiting from the rational design of SSEs, PIMs-based SSEs Li-metal batteries can achieve good cycling performance and superior feasibility in a series of withstand abuse tests including bending, cutting, and penetration. Moreover, the PIMs-based SSEs endow high specific capacity (11307â mAh g-1 ) and long-term discharge/charge stability (247â cycles) for solid-state Li-O2 batteries. The PIMs-based SSEs present a powerful strategy for enabling safe operation of high-energy solid-state batteries.
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OBJECTIVE: To analyze the effect of CD56 expression on the prognosis of newly diagnosed multiple myeloma (MM) patients and explore the relationship between CD56 with clinical characteristics. METHODS: In this retrospective study, the clinical data and laboratory parameters of 175 newly diagnosed MM patients from February 2015 to December 2020 in the Second Hospital of Anhui Medical University were collected. The patients were divided into CD56+ and CD56- groups based on the expression of CD56, and the general data and laboratory parameters of the two groups were compared. The patients were followed up to June 30, 2021, and progression-free survival (PFS) and overall survival (OS) were recorded. PFS and OS curves of the two groups were plotted respectively, and the survival differences were compared. Univariate and multivariate Cox regression analyses were performed to analyze the effect of CD56 on the prognosis of newly diagnosed MM patients. RESULTS: In 175 newly diagnosed MM patients, 57(32.6%) cases were in the CD56-group and 118 (67.4%) cases in the CD56+ group. There was significant correlation between CD56 expression and ISS stage, ECOG score, platelets, ß2-microglobulin, creatinine, and extramedullary disease (all P <0.05). The incidence of extramedullary disease in the CD56- group was significantly higher than that in the CD56+ group (29.8% vs 12.7%, P =0.006). The median follow-up time of the whole cohort was 23.6 (1.0-78.6) months. The median PFS of patients in CD56+ group and CD56- group were 18.6 (1.2-77.6) and 12.2 (1.0-49.0) months, respectively, and the median OS of the two groups were 27.6 (1.4-77.7) and 19.7 (1.0-78.6) months, respectively. The 2-year PFS rate in the CD56+ group was significantly higher than that in the CD56- group (57.6% vs 36.8%, P =0.010), and the 2-year OS rate in the CD56+ group was higher than that in the CD56- group, but it didn't reach statistical significance (74.6% vs 64.9%, P =0.158). The results of univariate Cox regression analysis showed that the PFS was significantly shorter in newly diagnosed MM patients with advanced age, type IgG, high ECOG score, decreased platelet count, increased lactate dehydrogenase level, extramedullary disease, and CD56- (all P <0.05), the OS was significantly shorter in patients with high ECOG score, decreased platelet count, increased lactate dehydrogenase level, extramedullary disease, and CD56- (all P <0.05). The results of multivariate Cox regression analysis showed that advanced age, type IgG, elevated lactate dehydrogenase level, extramedullary disease, and CD56- were independent prognostic factors for poor PFS (all P <0.05); and decreased platelet count, elevated lactate dehydrogenase level, and extramedullary disease were independent adverse prognostic factors for OS (all P <0.05), while there was no significant independent correlation between CD56 and OS (P >0.05). CONCLUSION: Most of the newly diagnosed MM patients have positive expression of CD56. Loss of CD56 expression was associated with unfavorable biological and clinical parameters and poor prognosis, suggesting that CD56 has important clinical value in the prognosis of newly diagnosed MM patients.
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Mieloma Múltiplo , Humanos , Imunoglobulina G , Lactato Desidrogenases , Mieloma Múltiplo/diagnóstico , Prognóstico , Estudos RetrospectivosRESUMO
To address the problems of low accuracy and slow convergence of traditional multilevel image segmentation methods, a symmetric cross-entropy multilevel thresholding image segmentation method (MSIPOA) with multi-strategy improved pelican optimization algorithm is proposed for global optimization and image segmentation tasks. First, Sine chaotic mapping is used to improve the quality and distribution uniformity of the initial population. A spiral search mechanism incorporating a sine cosine optimization algorithm improves the algorithm's search diversity, local pioneering ability, and convergence accuracy. A levy flight strategy further improves the algorithm's ability to jump out of local minima. In this paper, 12 benchmark test functions and 8 other newer swarm intelligence algorithms are compared in terms of convergence speed and convergence accuracy to evaluate the performance of the MSIPOA algorithm. By non-parametric statistical analysis, MSIPOA shows a greater superiority over other optimization algorithms. The MSIPOA algorithm is then experimented with symmetric cross-entropy multilevel threshold image segmentation, and eight images from BSDS300 are selected as the test set to evaluate MSIPOA. According to different performance metrics and Fridman test, MSIPOA algorithm outperforms similar algorithms in global optimization and image segmentation, and the symmetric cross entropy of MSIPOA algorithm for multilevel thresholding image segmentation method can be effectively applied to multilevel thresholding image segmentation tasks.
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Algoritmos , Humanos , Entropia , Processamento de Imagem Assistida por ComputadorRESUMO
BACKGROUND: Digital intraoral scanning, although developing rapidly, is rarely used in occlusal reconstruction. To compensate for the technical drawbacks of current occlusal reconstruction techniques, such as time consumption and high technical requirements, digital intraoral scanning can be used in clinics. This report aims to provide a way of selecting the most suitable maxillo-mandibular relationship (MMR) during recovery. CASE SUMMARY: A 68-year-old man with severely worn posterior teeth underwent occlusal reconstruction with fixed prosthesis using digital intraoral scanning. A series of digital models in different stages of treatment were obtained, subsequently compared, and selected using digital intraoral scanning together with traditional measurements, such as cone beam computed tomography, joint imaging, and clinical examination. Using digital intraoral scanning, the MMR in different stages of treatment was accurately recorded, which provided feasibility for deciding the best occlusal reconstruction treatment, made the treatment process easier, and improved patient satisfaction. CONCLUSION: This case report highlights the clarity, recordability, repeatability, and selectivity of digital intraoral scanning to replicate and transfer the MMR during occlusal reconstruction, expanding new perspectives for its design, fabrication, and postoperative evaluation.
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The demand for high-energy sustainable rechargeable batteries has motivated the development of lithium-oxygen (Li-O2) batteries. However, the inherent safety issues of liquid electrolytes and the sluggish reaction kinetics of existing cathodes remain fundamental challenges. Herein, we demonstrate a promising photo-assisted solid-state Li-O2 battery based on metal-organic framework-derived mixed ionic/electronic conductors, which simultaneously serve as the solid-state electrolytes (SSEs) and the cathode. The mixed conductors could effectively harvest ultraviolet-visible light to generate numerous photoelectrons and holes, which is favorable to participate in the electrochemical reaction, contributing to greatly improved reaction kinetics. According to the study on conduction behavior, we discover that the mixed conductors as SSEs possess outstanding Li+ conductivity (1.52 × 10-4 S cm-1 at 25 °C) and superior chemical/electrochemical stability (especially toward H2O, O2-, etc.). Application of mixed ionic electronic conductors in photo-assisted solid-state Li-O2 batteries further reveals that a high energy efficiency (94.2%) and a long life (320 cycles) can be achieved with a simultaneous design of SSEs and cathodes. The achievements present the widespread universality in accelerating the development of safe and high-performance solid-state batteries.
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Background: Nowadays, e-learning significantly affects college students' academic life. This study aims to examine the factors that influence college students' satisfaction with online learning outcomes. Method: The study population consisted of undergraduate students from Dalian Medical University, with a total of 715 college students participating in the study. Out of these participants, 602 valid questionnaires were obtained. Demographic data was analyzed using SPSS.22, and the data was cleaned and prepared for testing the research hypotheses. The proposed research framework was examined using structural equation modeling (SEM) through Smart-PLS 3.0. Results: The results of the study showed that student satisfaction with learning outcomes was positively correlated with several factors: quality of teacher instruction (ß = 0.100, p < 0.0001), quality of e-learning platforms (ß = 0.059, p < 0.0001), individual learner factors such as learning motivation (ß = 0.112, p < 0.001), and e-learning environment (ß = 0.469, p < 0.001). Additionally, self-learning efficacy (ß = 0.081, p < 0.0001), learning strategies (ß = 0.031, p < 0.001), and learning motivation (ß = 0.039, p < 0.001) were found to have mediating effects. Conclusion: Understanding the satisfaction of college students with the effect of e-learning holds great significance in coping with teaching methods in unexpected situations. It enables adjustments to teaching strategies, improvements to learning platforms, and mobilization of students' motivation. Thus, it serves as a valuable reference in addressing unexpected teaching scenarios.
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The design of highly efficient electrocatalysts is a promising strategy to improve the electrochemical kinetics of Li-CO2 batteries. However, electrocatalysts usually aim to reduce the energetic barrier for the corresponding electrochemical reactions; little attention has been given to modulating the kinetics that directly determine the local concentration of reaction molecules surrounding catalysts. Herein, we present a systematic study on the role of Li+ reunion on the improvement of reaction kinetics in Li-CO2 batteries with a Cu cone cathode. Specifically, this local, geometry-driven tip effect can enrich the local electron concentration to facilitate Li+ ions diffusion from the bulk electrolyte to the surface of catalyst, leading to boosted catalytic performance. Further studies demonstrate that Cu(II/I) as a solid redox mediator dominates the reversible bulk redox reactions in a Cu cone cathode, which acts as an electron-hole transfer agent and permits the efficient reduction and oxidation of solid Li2CO3, contributing to an accessible theoretical discharge voltage, low charge potential below 3.2 V, impressive rate capability, and a long cycling stability (333 days) for Li-CO2 batteries. The exploitation of the sharp-tip enhancement effect and dynamic creation of catalytic active sites is expected to become routine practice in future mechanistic studies for metal-air batteries.
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At present, photoassisted Li-air batteries are considered to be an effective approach to overcome the sluggish reaction kinetics of the Li-air batteries. And, the organic liquid electrolyte is generally adopted by the current conventional photoassisted Li-air batteries. However, the superior catalytic activity of photoassisted cathode would in turn fasten the degradation of the organic liquid electrolyte, leading to limited battery cycling life. Herein, we tame the above limitation of the traditional liquid electrolyte system for Li-CO2 batteries by constructing a photoassisted all-solid-state Li-CO2 battery with an integrated bilayer Au@TiO2/Li1.5Al0.5Ge1.5(PO4)3 (LAGP)/LAGP (ATLL) framework, which can essentially improve battery stability. Taking advantage of photoelectric and photothermal effects, the Au@TiO2/LAGP layer enables the acceleration of the slow kinetics of the carbon dioxide reduction reaction and evolution reaction processes. The LAGP layer could resolve the problem of liquid electrolyte decomposition under illumination. The integrated double-layer LAGP framework endows the direct transportation of heat and Li+ in the entire system. The photoassisted all-solid-state Li-CO2 battery achieves an ultralow polarization of 0.25 V with illumination, as well as a high round-trip efficiency of 92.4%. Even at an extremely low temperature of -73 °C, the battery can still deliver a small polarization of 0.6 V by converting solar energy into heat to achieve self-heating. This study is not limited to the Li-air batteries but can also be applied to other battery systems, constituting a significant step toward the practical application of all-solid-state photoassisted Li-air batteries.