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1.
J Am Chem Soc ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092859

RESUMEN

Searching for high energy-density electrode materials for sodium ion batteries has revealed Na-deficient intercalation compounds with lattice oxygen redox as promising high-capacity cathodes. However, anionic redox reactions commonly encountered poor electrochemical reversibility and unfavorable structural transformations during dynamic (de)sodiation processes. To address this issue, we employed lithium orbital hybridization chemistry to create Na-O-Li configuration in a prototype P2-layered Na43/60Li1/20Mg7/60Cu1/6Mn2/3O2 (P2-NaLMCM') cathode material. That Li+ ions, having low electronegativity, reside in the transition metal slabs serves to stimulate unhybridized O 2p orbitals to facilitate the stable capacity contribution of oxygen redox at high state of charge. The prismatic-type structure evolving to an intergrowth structure of the Z phase at high charging state could be simultaneously alleviated by reducing the electrostatic repulsion of O-O layers. As a consequence, P2-NaLMCM' delivers a high specific capacity of 183.8 mAh g-1 at 0.05 C and good cycling stability with a capacity retention of 80.2% over 200 cycles within the voltage range of 2.0-4.5 V. Our findings provide new insights into both tailoring oxygen redox chemistry and stabilizing dynamic structural evolution for high-energy battery cathode materials.

2.
Phys Chem Chem Phys ; 26(2): 1406-1427, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38112095

RESUMEN

First-principles calculations were performed to analyze the atomic structures and electrochemical energy storage properties of novel MoS2⊥boridene heterostructures by anchoring MoS2 nanoflakes on Mo4/3B2 and Mo4/3B2O2 monolayers. Both thermodynamic and thermal stabilities of each heterostructure were thoroughly evaluated from the obtained binding energies and through first-principles molecular dynamics simulations at room temperature, confirming the high formability of the heterostructures. The electrochemical properties of MoS2⊥Mo4/3B2 and MoS2⊥Mo4/3B2O2 heterostructures were investigated for their potential use as anodes for alkaline metal ion batteries (Li+, Na+ and K+). It was revealed that Li+ and Na+ can form multiple stable full adsorption layers on both heterostructures, while K+ forms only a single full adsorption layer. The presence of a negative electron cloud (NEC) contributes to the stabilization of a multi-layer adsorption mechanism. For all investigated alkaline metal ions, the predicted ion diffusion dynamics are relatively sluggish for the adsorbates in the first full adsorption layer on MoS2⊥boridene heterostructures due the relatively large migration energies (>0.50 eV), compared to those of second or third full adsorption layers (<0.30 eV). MoS2⊥Mo4/3B2O2 exhibited higher onset and mean open circuit voltages as anodes for alkaline metal-ion batteries than MoS2⊥Mo4/3B2 hybrids because of enhanced interactions between the adsorbate and the Mo4/3B2O2 monolayer with the presence of O-terminations. Tailoring the size and horizontal spacing between two neighboring MoS2 nano-flakes in heterostructures led to high theoretical capacities for LIBs (531 mA h g-1), SIBs (300 mA h g-1) and PIBs (131 mA h g-1) in the current study.

3.
Diagnostics (Basel) ; 13(3)2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36766501

RESUMEN

This prospective, single-center study evaluated the clinical utility of annenxin (Anx)A1 level as a biomarker for determining the severity of illness and predicting the risk of death in hospitalized patients with community-acquired pneumonia (CAP). A total of 105 patients (53 with severe [S]CAP, 52 with non-SCAP) were enrolled from December 2020 to June 2021. Demographic and clinical data were recorded. Serum AnxA1 concentration on days one and six after admission was measured by enzyme-linked immunosorbent assay. AnxA1 level at admission was significantly higher in SCAP patients than in non-SCAP patients (p < 0.001) irrespective of CAP etiology and was positively correlated with Pneumonia Severity Index and Confusion, Uremia, Respiratory Rate, Blood Pressure, and Age ≥ 65 Years score. AnxA1 level was significantly lower on day six after treatment than on day one (p = 0.01). Disease severity was significantly higher in patents with AnxA1 level ≥254.13 ng/mL than in those with a level <254.13 ng/mL (p < 0.001). Kaplan-Meier analysis of 30-day mortality showed that AnxA1 level ≤670.84 ng/mL was associated with a significantly higher survival rate than a level >670.84 ng/mL. These results indicate that AnxA1 is a useful biomarker for early diagnosis and prognostic assessment of CAP.

4.
J BUON ; 24(6): 2546-2552, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31983131

RESUMEN

PURPOSE: This study aimed to compare the application value of midline catheter and peripherally inserted central catheter (PICC) in patients with gastrointestinal tumors during the perioperative period. METHODS: 487 patients with gastrointestinal tumors admitted to Qingdao Municipal Hospital from August 2016 to September 2018 were selected and retrospectively analyzed. 279 patients treated with midline catheters during the treatment were regarded as the study group, and another 208 patients treated with PICC were regarded as the control group. The incidence of perioperative adverse reactions, the cost of daily catheter maintenance and the the total cost of catheter indwelling were compared between the two groups. Meanwhile, each patient was investigated for treatment satisfaction at the time of discharge. RESULTS: The total incidence of adverse reactions in the study group was significantly lower than that in the control group (p=0.0001). The catheter indwelling duration in the study group was significantly shorter than that in the control group (p<0.001). The 24-h drainage volume in the study group was significantly higher than that in the control group (p<0.001). The average cost of daily maintenance and total cost of catheter indwelling in the study group were significantly lower than those in the control group (p<0.001). The satisfaction rate in the study group (69.53%) was significantly higher than that in the control group (51.92%) (p<0.001). The dissatisfaction rate in the study group (3.23%) was significantly lower than that in the control group (15.38%) (p<0.001). CONCLUSION: Compared with PICC, the perioperative application of midline catheter in patients with gastrointestinal tumors can effectively reduce catheter-related adverse reactions, with higher medical economic benefits and satisfaction rate, and is worthy of clinical promotion and application.


Asunto(s)
Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Catéteres de Permanencia/efectos adversos , Neoplasias Gastrointestinales/cirugía , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Estudios de Casos y Controles , Cateterismo Venoso Central/economía , Cateterismo Venoso Central/instrumentación , Cateterismo Periférico/economía , Cateterismo Periférico/instrumentación , Catéteres de Permanencia/economía , Femenino , Estudios de Seguimiento , Neoplasias Gastrointestinales/patología , Humanos , Masculino , Persona de Mediana Edad , Atención Perioperativa , Complicaciones Posoperatorias/patología , Pronóstico , Estudios Retrospectivos
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