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1.
Small ; : e2309580, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705865

RESUMO

Li-ion batteries with superior interior thermal management are crucial to prevent thermal runaway and ensure safe, long-lasting operation at high temperatures or during rapid discharging and charging. Typically, such thermal management is achieved by focusing on the separator and electrolyte. Here, the study introduces a Se-terminated MXene free-standing electrode with exceptional electrical conductivity and low infrared emissivity, synergistically combining high-rate capacity with reduced heat radiation for safe, large, and fast Li+ storage. This is achieved through a one-step organic Lewis acid-assisted gas-phase reaction and vacuum filtration. The Se-terminated Nb2Se2C outperformed conventional disordered O/OH/F-terminated materials, enhancing Li+-storage capacity by ≈1.5 times in the fifth cycle (221 mAh·g-1 at 1 A·g-1) and improving mid-infrared adsorption with low thermal radiation. These benefits result from its superior electrical conductivity, excellent structural stability, and high permittivity in the infrared region. Calculations further reveal that increased permittivity and conductivity along the z-direction can reduce heat radiation from electrodes. This work highlights the potential of surface groups-terminated layered material-based free-standing flexible electrodes with self-thermal management ability for safe, fast energy storage.

2.
Chemistry ; 24(68): 17897-17901, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30412309

RESUMO

Boron difluoroquinazolinone-pyridine (BODIQPy) and substituted derivatives have been designed and synthesized. Strong emission with high fluorescence quantum yield both in solution (up to 0.99) and in solid state (up to 0.60) was achieved in these asymmetric BODIQPys. For 6-halogen substituted BODIQPys, the heavy atomic effect of bromine and iodine was suppressed in solution due to the strong electron-withdrawing ability of the BODIQPy core. As a result, 6-iodine substituted BODIQPy shows the unusual fluorescence quantum yields (>0.70) in dichloromethane and tetrahydrofuran. In the solid state, the asymmetric structure induced a unique dimeric structure, and efficient luminescence was also observed. The formation of halogen bonds between carbonyl oxygen and bromine or iodine regulated the stacking mode and enhanced intermolecular interaction, resulting in a decline in the fluorescence quantum yield. In addition, a large Stokes shift was also achieved in these asymmetric BODIQPys.

3.
J Asthma Allergy ; 15: 939-955, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859665

RESUMO

Objective: This paper aims to perform a systematic assessment of the influence of physical exercise on asthma patients and discuss the intervention effects of different exercises on the lung function FEV1 (%pred) and quality of life among asthma patients so as to lay a scientific foundation for improving asthma symptoms. Methods: Both Chinese and English databases were retrieved, including PubMed, Web of Science, Embase, The Cochrane Library, CBM, CNKI, Wan Fang Data, and VIP, whose retrieval period started from the founding date of each database to 1st, November 2021. Randomized controlled trials (RCT) studying the symptom indicators of asthma patients were collected. Those collected papers were screened according to the Inclusion Criteria and Exclusion Criteria. Then, methodological quality assessments were conducted on the included papers, and combined effect sizes were analyzed by using software ReMan 5.3.5. Results: The meta analysis showed that physical exercise could significantly improve lung function FEV1 (%pred) and quality of life score. Trails containing breathing exercise are the main source of heterogeneity, and the subgroup of breathing exercise may have better performance than the subgroup of aerobic exercise in improving FEV1 (%pred). Conclusion: Physical exercise can significantly improve the symptoms and quality of life of asthma patients. Except the breathing exercise that showed heterogeneity, the subgroup of aerobic exercise could improve the capacity of FEV1 (%pred) more effectively, which led to a significant difference in the influence of quality of life. However, with regard to the gymnastic exercise including breathing exercise, there are limited same intervention methods and insufficient same outcome indicators. Therefore, more precise and high-quality researches are needed to make deeper verification in the future.

4.
ACS Appl Mater Interfaces ; 12(27): 30882-30889, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32525648

RESUMO

In this work, we proposed a new strategy of fabricating time-resolved fluorescent nanoprobes by using an enzyme-integrated lanthanide coordination polymer (CP) composite for the detection of superoxide anions (O2•-). This CP composite was constructed with terbium ions (Tb3+) as a metal node, adenosine triphosphate (ATP) as a bridge ligand, and carboxyphenylboronic acid (CPBA) as a sensitizer in which superoxide dismutase (SOD) was encapsulated by a self-adaptive inclusion process. The as-prepared SOD@ATP/Tb-CPBA displays both catalytic and fluorescence properties. Benefiting from the shielding effect of ATP/Tb CP, greatly enhanced catalytic activity and stability against harsh environments can be obtained in the loaded SOD. Meanwhile, the loaded SOD can remove the water molecules on the coordination sphere of Tb3+, leading to a significant increase in the fluorescence intensity and lifetime of SOD@ATP/Tb-CPBA. However, upon the addition of O2•-, the fluorescence of SOD@ATP/Tb-CPBA was quenched significantly. This is because SOD can convert O2•- into H2O2 to induce the deboronation of CPBA, resulting in an intramolecular charge transfer process. On this basis, by taking advantage of Tb3+ in long lifetime emission, a time-resolved fluorescence method was developed for the detection of O2•-, and satisfactory results have been achieved in both buffered aqueous solutions and serum samples. We believe that the presented study will open up a new avenue to develop enzyme-involved fluorescent nanoprobes.

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