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1.
COPD ; 21(1): 2369541, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39087240

RESUMO

To investigate the clinical effects and application value of self-made disseminating and descending breathing exercises on home rehabilitation of patients with stable chronic obstructive pulmonary disease (COPD). Seeking to generate concepts for creating novel, convenient, and efficient COPD prognosis rehabilitation exercises aimed at enhancing the well-being and rehabilitation confidence of both COPD patients and their families. A total of 70 COPD patients admitted to our outpatient department from July 2019 to September 2021 were randomly divided into the exercise group (n = 35) and the control group (n = 35). The control group received routine breathing training, while the exercise group was treated with self-made disseminating and descending breathing exercises. The respiratory function, including pulmonary function (FVC, FEV1, FEV1/FVC) and respiratory muscle strength (MIP, MEP), exercise tolerance (6-min walking distance, 6MWT), Modified Medical Research Council Dyspnea Scale (mMRC, Borg), COPD quality of life score (CAT, SGRQ), anxiety and depression scores (HAMA, HAMD) were compared between the two groups after 12-week exercise. After 12-week training, the FEV1, MIP, and MEP in the exercise group were significantly higher than those in the control group (p < 0.001), and the 6MWT was significantly increased in the exercise group compared to the control group (p < 0.001); while the mMRC, Borg score, the scores of CAT, SGRQ, HAMA, and HAMD were found significantly lower than those in the control group (p < 0.001). The self-made disseminating and descending breathing exercises can improve respiratory function and reduce symptoms of dyspnea in COPD patients, while enhancing exercise tolerance and relieving anxiety and depression, and are worthy of clinical application.


Assuntos
Exercícios Respiratórios , Tolerância ao Exercício , Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Humanos , Doença Pulmonar Obstrutiva Crônica/reabilitação , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Masculino , Feminino , Exercícios Respiratórios/métodos , Idoso , Pessoa de Meia-Idade , Dispneia/etiologia , Dispneia/reabilitação , Força Muscular , Depressão , Ansiedade/etiologia , Músculos Respiratórios/fisiopatologia , Teste de Caminhada , Volume Expiratório Forçado
2.
Chem Sci ; 15(31): 12189-12199, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39118610

RESUMO

Potassium-ion batteries (PIBs) are considered potential candidates for large-scale energy storage systems due to the abundant resources of potassium. Among various reported anode materials, bismuth anodes with the advantages of high theoretical specific capacity, low cost, and nontoxicity have attracted widespread attention. However, bismuth anodes experience significant volume changes during the charge/discharge process, leading to unsatisfactory cycling stability and rate performance. In this review, we focus on summarizing the research progress of bismuth anodes in PIBs. We discuss in detail the modification strategies for bismuth anodes in PIBs, including electrolyte optimization, morphology design, and hybridization with carbon materials. In addition, we attempt to propose possible future directions for the development of bismuth anodes in PIBs, aiming to expedite their practical application. It is believed that this review can assist researchers in more efficiently designing high-performance bismuth anode materials for PIBs.

3.
J Thorac Dis ; 16(7): 4238-4249, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39144338

RESUMO

Background: Distinguishing benign from malignant sub-centimeter solid pulmonary nodules (SSPNs) continues to be challenging in clinical practice. Earlier diagnosis is crucial for improving patient survival and prognosis. This study aimed to investigate the risk factors of malignant SSPNs and establish and validate a prediction model based on computed tomography (CT) characteristics to assist in their early diagnosis. Methods: A total of 261 consecutive participants with 261 SSPNs were retrospectively recruited between January 2012 and July 2023 from National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (Center 1), including 161 malignant lesions and 100 benign lesions. Patients were randomly assigned to the training set (n=183) and validation set (n=78) according to a 7:3 ratio. Malignant nodules were confirmed by pathology; and benign nodules were confirmed by follow-up or pathology. Clinical data and CT features were collected to estimate the independent predictors of malignancy of SSPN with multivariate logistic analysis. A clinical prediction model was subsequently established by logistic regression. Furthermore, an additional 69 consecutive patients with 69 SSPNs from The Fourth Hospital of Hebei Medical University (Center 2) between January 2022 and December 2022 were retrospectively included as an external cohort to validate the predictive efficacy of the model. The performance of the prediction model was assessed by sensitivity, specificity, and the area under the receiver operating characteristic curve. Results: There were 113 (61.7%), 48 (61.5%) and 28 (40.6%) malignant SSPNs in the training, internal and external validation sets, respectively. Multivariate logistic analysis revealed four independent predictors of malignant SSPNs: tumor-lung interface (P=0.002), spiculation (P=0.04), air bronchogram (P=0.047), and invisible at the mediastinal window (P=0.003). The area under the curve (AUC) for the prediction model in the training set was 0.875 [95% confidence interval (CI): 0.818, 0.933]; and the sensitivity and specificity were 94.7% and 68.6%, respectively. The AUCs in the internal and external validation set were (0.781; 95% CI: 0.664, 0.897) and (0.873; 95% CI: 0.791, 0.955), respectively; the sensitivity and specificity were 66.7% and 83.3% for the internal validation data, and 100.0% and 61.0% for the external validation data, respectively. Conclusions: The prediction model based on CT characteristics could be helpful for distinguishing malignant SSPNs from benign ones.

5.
Int J Pharm ; : 124582, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39142466

RESUMO

Chemotherapy agents for lung cancer often cause apoptotic resistance in cells, leading to suboptimal therapeutic outcomes. FIN56 can be a potential treatment for lung cancer as it induces non-apoptotic cell death, namely ferroptosis. However, a bottleneck exists in FIN56-induced ferroptosis treatment; specifically, FIN56 fails to induce sufficient oxidative stress and may even trigger the defense system against ferroptosis, resulting in poor therapeutic efficacy. To overcome this, this study proposed a strategy of co-delivering FIN56 and piperlongumine to enhance the ferroptosis treatment effect by increasing oxidative stress and connecting with the autophagy pathway. FIN56 and piperlongumine were encapsulated into silk fibroin-based nano-disruptors, named FP@SFN. Characterization results showed that the particle size of FP@SFN was in the nanometer range and the distribution was uniform. Both in vivo and in vitro studies demonstrated that FP@SFN could effectively eliminate A549 cells and inhibit subcutaneous lung cancer tumors. Notably, ferroptosis and autophagy were identified as the main cell death pathways through which the nano-disruptors increased oxidative stress and facilitated cell membrane rupture. In conclusion, nano-disruptors can effectively enhance the therapeutic effect of ferroptosis treatment for lung cancer through the ferroptosis-autophagy synergy mechanism, providing a reference for the development of related therapeutics.

6.
Chemistry ; : e202304106, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083260

RESUMO

Sodium-oxygen batteries have been regarded as promising energy storage devices due to their low overpotential and high energy density. Its applications, however, still face formidable challenges due to the lack of understanding about the influence of electrocatalysts on the discharge products. Here, a phosphorous and nitrogen dual-doped carbon (PNDC) based cathode is synthesized to increase the electrocatalytic activity and to stabilize the NaO2 superoxide nanoparticle discharge products, leading to enhanced cycling stability when compared to the nitrogen-doped carbon (NDC). The PNDC air cathode exhibits a low overpotential (0.36 V) and long cycling stability (120 cycles). The reversible formation/decomposition and stabilization of the NaO2 discharge products are clearly proven by in-situ synchrotron X-ray diffraction and ex-situ X-ray diffraction. Based on the density functional theory calculation, the PNDC has much stronger adsorption energy (-2.85 eV) for NaO2 than that of NDC (-1.80 eV), which could efficiently stabilize the NaO2 discharge products.

7.
Chem Sci ; 15(29): 11302-11310, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39055028

RESUMO

High-voltage LiNi0.5Mn1.5O4 (LNMO) is one of the most promising cathode candidates for rechargeable lithium-ion batteries (LIBs) but suffers from deteriorated cycling stability due to severe interfacial side reactions and manganese dissolution. Herein, a micro-nano porous spherical LNMO cathode was designed for high-performance LIBs. The disordered structure and the preferred exposure of the {111} facets can be controlled by the release of lattice oxygen in the high-temperature calcination process. The unique configuration of this material could enhance the structural stability and play a crucial role in inhibiting manganese dissolution, promoting the rapid transport of Li+, and reducing the volume strain during the charge/discharge process. The designed cathode exhibits a remarkable discharge capacity of 136.7 mA h g-1 at 0.5C, corresponding to an energy density of up to 636.4 W h kg-1, unprecedented cycling stability (capacity retention of 90.6% after 500 cycles) and superior rate capability (78.9% of initial capacity at 10C). The structurally controllable preparation strategy demonstrated in this work provides new insights into the structural design of cathode materials for LIBs.

8.
N Engl J Med ; 391(3): 213-223, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39018531

RESUMO

BACKGROUND: The efficacy and safety of risankizumab as compared with ustekinumab in patients with Crohn's disease are unknown. METHODS: In this phase 3b, multicenter, open-label, randomized, controlled trial with blinded assessment of end points, patients with moderate-to-severe Crohn's disease who had had an inadequate response to anti-tumor necrosis factor (TNF) therapy or unacceptable side effects with such therapy were randomly assigned to receive risankizumab or ustekinumab at standard doses for 48 weeks. The two primary end points, which were tested sequentially, were clinical remission at week 24 (defined as a Crohn's Disease Activity Index score of <150 [range, 0 to 600, with higher scores indicating more severe disease activity]), which was analyzed in the first 50% of patients to complete the week 24 visit, with a noninferiority margin of 10 percentage points; and endoscopic remission at week 48 (defined as a score of ≤4, a decrease of ≥2 points from baseline, and no subscore >1 in any individual variable on the Simple Endoscopic Score for Crohn's Disease [range, 0 to 56, with higher scores indicating more severe disease]), which was analyzed for superiority in 100% of the patients. Safety was assessed in all patients who received at least one dose of risankizumab or ustekinumab. RESULTS: In the full intention-to-treat population for the efficacy analysis, 230 of 255 patients (90.2%) who received risankizumab and 193 of 265 patients (72.8%) who received ustekinumab completed all the assigned treatments. Both primary end points were met; risankizumab was noninferior to ustekinumab with respect to clinical remission at week 24 (58.6% vs. 39.5%; adjusted difference, 18.4 percentage points; 95% confidence interval [CI], 6.6 to 30.3) and superior to ustekinumab with respect to endoscopic remission at week 48 (31.8% vs. 16.2%; adjusted difference, 15.6 percentage points; 95% CI, 8.4 to 22.9; P<0.001). The incidence of adverse events appeared to be similar in the two groups. CONCLUSIONS: In this head-to-head clinical trial of risankizumab and ustekinumab involving patients with moderate-to-severe Crohn's disease who had had unacceptable side effects with anti-TNF therapy or an inadequate response to such therapy, risankizumab was noninferior to ustekinumab with respect to clinical remission at week 24 and superior with respect to endoscopic remission at week 48. (Funded by AbbVie; ClinicalTrials.gov number, NCT04524611.).


Assuntos
Anticorpos Monoclonais , Doença de Crohn , Indução de Remissão , Ustekinumab , Humanos , Doença de Crohn/tratamento farmacológico , Ustekinumab/uso terapêutico , Ustekinumab/efeitos adversos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Índice de Gravidade de Doença , Análise de Intenção de Tratamento , Adulto Jovem
9.
JAMA ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037800

RESUMO

Importance: The clinical effects of risankizumab (a monoclonal antibody that selectively targets the p19 subunit of IL-23) for the treatment of ulcerative colitis are unknown. Objective: To evaluate the efficacy and safety of risankizumab when administered as an induction and a maintenance therapy for patients with ulcerative colitis. Design, Setting, and Participants: Two phase 3 randomized clinical trials were conducted. The induction trial was conducted at 261 clinical centers (in 41 countries) and enrolled 977 patients from November 5, 2020, to August 4, 2022 (final follow-up on May 16, 2023). The maintenance trial was conducted at 238 clinical centers (in 37 countries) and enrolled 754 patients from August 28, 2018, to March 30, 2022 (final follow-up on April 11, 2023). Eligible patients had moderately to severely active ulcerative colitis; a history of intolerance or inadequate response to 1 or more conventional therapies, advanced therapies, or both types of therapies; and no prior exposure to risankizumab. Interventions: For the induction trial, patients were randomized 2:1 to receive 1200 mg of risankizumab or placebo administered intravenously at weeks 0, 4, and 8. For the maintenance trial, patients with a clinical response (determined using the adapted Mayo score) after intravenous treatment with risankizumab were randomized 1:1:1 to receive subcutaneous treatment with 180 mg or 360 mg of risankizumab or placebo (no longer receiving risankizumab) every 8 weeks for 52 weeks. Main Outcomes and Measures: The primary outcome was clinical remission (stool frequency score ≤1 and not greater than baseline, rectal bleeding score of 0, and endoscopic subscore ≤1 without friability) at week 12 for the induction trial and at week 52 for the maintenance trial. Results: Among the 975 patients analyzed in the induction trial (aged 42.1 [SD, 13.8] years; 586/973 [60.1%] were male; and 677 [69.6%] were White), the clinical remission rates at week 12 were 132/650 (20.3%) for 1200 mg of risankizumab and 20/325 (6.2%) for placebo (adjusted between-group difference, 14.0% [95% CI, 10.0%-18.0%], P < .001). Among the 548 patients analyzed in the maintenance trial (aged 40.9 [SD, 14.0] years; 313 [57.1%] were male; and 407 [74.3%] were White), the clinical remission rates at week 52 were 72/179 (40.2%) for 180 mg of risankizumab, 70/186 (37.6%) for 360 mg of risankizumab, and 46/183 (25.1%) for placebo (adjusted between-group difference for 180 mg of risankizumab vs placebo, 16.3% [97.5% CI, 6.1%-26.6%], P < .001; adjusted between-group difference for 360 mg of risankizumab vs placebo, 14.2% [97.5% CI, 4.0%-24.5%], P = .002). No adverse event signals were detected in the treatment groups. Conclusion and Relevance: Compared with placebo, risankizumab improved clinical remission rates in an induction trial and in a maintenance trial for patients with moderately to severely active ulcerative colitis. Further study is needed to identify benefits beyond the 52-week follow-up. Trial Registration: ClinicalTrials.gov Identifiers: NCT03398148 and NCT03398135.

10.
Entropy (Basel) ; 26(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39056917

RESUMO

This paper proposes a novel censored autoregressive conditional Fréchet (CAcF) model with a flexible evolution scheme for the time-varying parameters, which allows deciphering tail risk dynamics constrained by price limits from the viewpoints of different risk preferences. The proposed model can well accommodate many important empirical characteristics of financial data, such as heavy-tailedness, volatility clustering, extreme event clustering, and price limits. We then investigate tail risk dynamics via the CAcF model in the price-limited stock markets, taking entropic value at risk (EVaR) as a risk measurement. Our findings suggest that tail risk will be seriously underestimated in price-limited stock markets when the censored property of limit prices is ignored. Additionally, the evidence from the Chinese Taiwan stock market shows that widening price limits would lead to a decrease in the incidence of extreme events (hitting limit-down) but a significant increase in tail risk. Moreover, we find that investors with different risk preferences may make opposing decisions about an extreme event. In summary, the empirical results reveal the effectiveness of our model in interpreting and predicting time-varying tail behaviors in price-limited stock markets, providing a new tool for financial risk management.

11.
J Hazard Mater ; 476: 135228, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39024761

RESUMO

Peroxidase-like (POD-like) as a kind of new Fenton-like catalyst can effectively activate H2O2 to degrade organic pollutants in water, but improving the catalytic activity and stability of POD-like remains a challenging task. Here, we synthesized a novel dual single-atom nanoenzyme (DSAzyme) FeMn/N-CNTs with Fe-N4 and Mn-N4 bimetallic single-atom active centers by mimicking the active centers of natural enzymes and taking advantage of the synergistic effect between the dual metals. FeMn/N-CNTs DSAzyme showed significantly enhanced POD-like activity compared to monometallic-loaded Fe/N-CNTs and Mn/N-CNTs. Within the FeMn/N-CNTs/H2O2 system, bisphenol A (BPA) could be removed 100 % within 20 min. DFT calculations show that Mn-N4 in FeMn/N-CNTs can readily adsorb negatively charged BPA molecules and capture electrons. Meanwhile, Fe-N4 sites can easily adsorb H2O2 molecules, leading to their activation and splitting into strongly oxidizing hydroxyl radicals (·OH). Throughout this process, electrons are continuously recycled in BPA → Mn-N4 → Fe-N4 → H2O2, effectively promoting the regeneration of Fe2+. Practical studies on wastewater and cycling experiments have demonstrated the great potential of this method for remediating water environments.


Assuntos
Compostos Benzidrílicos , Peróxido de Hidrogênio , Ferro , Manganês , Fenóis , Poluentes Químicos da Água , Compostos Benzidrílicos/química , Ferro/química , Fenóis/química , Peróxido de Hidrogênio/química , Manganês/química , Poluentes Químicos da Água/química , Nanotubos de Carbono/química , Elétrons , Catálise , Águas Residuárias/química , Peroxidase/química , Peroxidase/metabolismo , Purificação da Água/métodos
12.
Plants (Basel) ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38999599

RESUMO

Dicranum Hedw. is a highly diverse and widely distributed genus within Dicranaceae. The species diversity and distribution of this genus in China, however, remain not well known. A new revision of Dicranum in China using morphological and molecular phylogenetic methods confirms that China has 39 species, including four newly reported species, D. bardunovii Tubanova & Ignatova, D. dispersum Engelmark, D. schljakovii Ignatova & Tubanova, and D. spadiceum J.E.Zetterst. Dicranum psathyrum Klazenga is transferred to Dicranoloma (Renauld) Renauld as a new synonym of Dicranoloma fragile Broth. Two species, Dicranum brevifolium (Lindb.) Lindb. and D. viride (Sull. & Lesq.) Lindb. are excluded from the bryoflora of China. A key to the Chinese Dicranum species is also provided. These results indicate an underestimation of the distribution range of numerous Dicranum species, underscoring the need for further in-depth investigations into the worldwide Dicranum diversity.

13.
Phys Rev Lett ; 132(25): 256503, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38996236

RESUMO

The recently discovered superconductivity with critical temperature T_{c} up to 80 K in the double-layer Nickelate La_{3}Ni_{2}O_{7-δ} under pressure has drawn great attention. Here, we report the positive muon spin relaxation (µ^{+}SR) study of polycrystalline La_{3}Ni_{2}O_{6.92} under ambient pressure. Zero-field µ^{+}SR experiments reveal the existence of magnetic order in La_{3}Ni_{2}O_{6.92} with T_{N}=154 K. The weak transverse field µ^{+}SR measurements reveal the bulk nature of magnetism. In addition, a small quantity of oxygen deficiencies can greatly broaden the internal magnetic field distribution sensed by muons.

14.
Chem Commun (Camb) ; 60(51): 6496-6499, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38836703

RESUMO

Cobalt substitution for manganese sites in Na0.44MnO2 initiates a dynamic structural evolution process, yielding a composite cathode material comprising intergrown P2 and P3 phases. The novel P2/P3 composite cathode exhibits a reversible phase transition process during Na+ extraction/insertion, showcasing its attractive battery performance in sodium-ion batteries.

15.
Inorg Chem ; 63(25): 11592-11603, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38861349

RESUMO

In order to take advantage of the distinct reversible multielectron transfer properties of polyoxometalates (POMs) and increase the electron density at the active sites during the electrochemical reduction of CO2 (CO2RR), a range of transition metal-doped polyoxometalates (TMSPOMs) was entrapped within the porphyrin-based framework of PCN-224 via an encapsulation method, known as TMSPOMs@PCN-224 (TMSPOMs = [XW11O39MII(H2O)]n-, [XW11O40VIV]n-, M = CoII, MnII; X = Si, n = 6; X = P, n = 5). The central elements (Si, P) and the incorporated transition metals (VIV, CoII, and MnII) both play a role in adjusting the electronic structure and electron transfer during the CO2RR process. Remarkably, the composite material with cobalt substitution displayed significantly improved performance. Through fine-tuning the POM loading, the electrocatalytic activity was optimized, leading to an impressive Faradaic efficiency for CO production (FECO) of 89.9% for SiW11Co@PCN-224, a significant improvement compared to the 12.1% FECO of PCN-224. Furthermore, the electrochemical stability of this catalyst was demonstrated over 20 h. Comparative analyses involving six composite materials indicated a relationship between the negative charge of the polyanions and their ability to facilitate effective electron transfer, ultimately enhancing the catalyst's performance. Meanwhile, these findings were supported by density functional theory (DFT) calculations.

16.
Environ Sci Technol ; 58(26): 11256-11267, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38885093

RESUMO

Short-term exposure to particles with aerodynamic diameters less than 2.5 µm (PM2.5) and ozone (O3) are important risk factors for human health. Despite the awareness of reducing attributable health burden, region-specific and source-specific strategies remain less explored due to the gap between precursor emissions and health effects. In this study, we isolate the health burden of individual sector sources of PM2.5 and O3 precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), across the globe. Specifically, we estimate mortalities attributable to short-term exposure using machine-learning-based daily exposure estimates and quantify sectoral impacts using chemical transport model simulations. Globally, short-term exposure to PM2.5 and O3 result in 713.5 (95% Confidence Interval: 598.8-843.3) thousand and 496.3 (371.3-646.1) thousand mortalities in 2019, respectively, of which 12.5% are contributed by fuel-related NOx emissions from transportation, energy, and industry. Sectoral impacts from anthropogenic NOx and VOC emissions on health burden vary significantly among seasons and regions, requiring a target shift from transportation in winter to industry in summer for East Asia, for instance. Emission control and health management are additionally complicated by unregulated natural influences during climatic events. Fire-sourced NOx and VOC emissions, respectively, contribute to 8.5 (95% CI: 6.2-11.7) thousand and 4.8 (3.6-5.9) thousand PM2.5 and O3 mortalities, particularly for tropics with high vulnerability to climate change. Additionally, biogenic VOC emissions during heatwaves contribute to 1.8 (95% CI: 1.5-2.2) thousand O3-introduced mortalities, posing challenges in urban planning for high-income regions, where biogenic contributions to health burden during heatwaves are 13% of anthropogenic contributions annually. Our study provides important implications for temporally dynamic and sector-targeted emission control and health management strategies, which are of urgency under the projection of continuously increasing energy consumption and changing climate.


Assuntos
Poluentes Atmosféricos , Ozônio , Material Particulado , Humanos , Exposição Ambiental , Compostos Orgânicos Voláteis , Óxidos de Nitrogênio
17.
Chem Sci ; 15(22): 8478-8487, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38846387

RESUMO

Hard carbon (HC) is one of the most promising anode materials for sodium-ion batteries (SIBs) due to its cost-effectiveness and low-voltage plateau capacity. Heteroatom doping is considered as an effective strategy to improve the sodium storage capacity of HC. However, most of the previous heteroatom doping strategies are performed at a relatively low temperature, which could not be utilized to raise the low-voltage plateau capacity. Moreover, extra doping of heteroatoms could create new defects, leading to a low initial coulombic efficiency (ICE). Herein, we propose a repair strategy based on doping a trace amount of P to achieve a high capacity along with a high ICE. By employing the cross-linked interaction between glucose and phytic acid to achieve the in situ P doped spherical hard carbon, the obtained PHC-0.2 possesses a large interlayer space that facilitates Na+ storage and transportation. In addition, doping a suitable amount of P could repair some defects in carbon layers. When used as an anode material for SIBs, the PHC-0.2 exhibits an enhanced reversible capacity of 343 mA h g-1 at 20 mA g-1 with a high ICE of 92%. Full cells consisting of a PHC-0.2 anode and a Na2Fe0.5Mn0.5[Fe(CN)6] cathode exhibited an average potential of 3.1 V with an initial discharge capacity of 255 mA h g-1 and an ICE of 85%. The full cell displays excellent cycling stability with a capacity retention of 80.3% after 170 cycles. This method is simple and low-cost, which can be extended to other energy storage materials.

19.
ACS Nano ; 18(20): 12945-12956, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717846

RESUMO

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+ kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3-O3' phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

20.
Nat Commun ; 15(1): 4064, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744875

RESUMO

Events of stratospheric intrusions to the surface (SITS) can lead to severe ozone (O3) pollution. Still, to what extent SITS events impact surface O3 on a national scale over years remains a long-lasting question, mainly due to difficulty of resolving three key SITS metrics: frequency, duration and intensity. Here, we identify 27,616 SITS events over China during 2015-2022 based on spatiotemporally dense surface measurements of O3 and carbon monoxide, two effective indicators of SITS. An overview of the three metrics is presented, illustrating large influences of SITS on surface O3 in China. We find that SITS events occur preferentially in high-elevation regions, while those in plain regions are more intense. SITS enhances surface O3 by 20 ppbv on average, contributing to 30-45% of O3 during SITS periods. Nationally, SITS-induced O3 peaks in spring and autumn, while over 70% of SITS events during the warm months exacerbate O3 pollution. Over 2015-2022, SITS-induced O3 shows a declining trend. Our observation-based results can have implications for O3 mitigation policies in short and long terms.

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