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1.
RSC Adv ; 14(17): 11862-11871, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38623293

RESUMO

Since Na3V2(PO4)3 (NVP) possesses modest volume deformation and three-dimensional ion diffusion channels, it is a potential sodium-ion battery cathode material that has been extensively researched. Nonetheless, NVP still endures the consequences of poor electronic conductivity and low voltage platforms, which need to be further improved. On this basis, a high voltage platform Na3V2(PO4)2F3 was introduced to form a composite with NVP to increase the energy density. In this study, the sol-gel technique was successfully used to synthesize a Na3V2(PO4)2.75F0.75/C (NVPF·3NVP/C) composite cathode material. The citric acid-derived carbon layer was utilized to construct three-dimensional conducting networks to effectively promote ion and electron diffusion. Furthermore, the composites' synergistic effect accelerates the quick ionic migration and improves the kinetic reaction. In particular, NVP as the dominant phase enhanced the structural stability and significantly increased the capacitive contribution. Therefore, at 0.1C, the discharge capacity of the modified NVPF·3NVP/C composite is 120.7 mA h g-1, which is greater than the theoretical discharge capacity of pure NVP (118 mA h g-1). It discharged 110.9 mA h g-1 of reversible capacity even at an elevated multiplicity of 10C, and after 200 cycles, it retained 64.1% of its capacity. Thus, the effort produced an optimized NVPF·3NVP/C composite cathode material that may be used in the sodium ion cathode.

2.
ACS Appl Mater Interfaces ; 16(5): 6143-6151, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270105

RESUMO

V5S8 has received extensive attention in the field of sodium-ion batteries (SIBs) due to its two-dimensional (2D) layered structure, and weak van der Waals forces between V-S accelerate the transport of sodium ions. However, the long-term cycling of V5S8 still suffers from volume expansion and low conductivity. Herein, a hollow nanotube V5S8@C (H-V5S8@C) with improved conductivity was synthesized by a solvothermal method to alleviate cracking caused by volume expansion. Benefiting from the large specific surface area of the hollow nanotube structure and uniform carbon coating, H-V5S8@C exhibits a more active site and enhanced conductivity. Meanwhile, the heterojunction formed by a few residual MoS2 and the outer layer of V5S8 stabilizes the structure and reduces the ion migration barrier with fast Na+ transport. Specifically, the H-V5S8@C anode provides an enhanced rate performance of 270.1 mAh g-1 at 15 A g-1 and high cycling stability of 291.7 mAh g-1 with a retention rate of 90.98% after 300 cycles at 5 A g-1. This work provides a feasible approach for the structural design of 2D layered materials, which can promote the practical application of fast-charging sodium-ion batteries.

3.
Front Chem ; 6: 174, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29876346

RESUMO

Reduced graphene oxide (rGO) sheet decorated Na3V2(PO4)3 (NVP) microspheres were successfully synthesized by spray-drying method. The NVP microspheres were embedded by rGO sheets, and the surface of the particles were coated by rGO sheets and amorphous carbon. Thus, the carbon conductive network consisted of rGO sheets and amorphous carbon generated in the cathode material. NVP microspheres decorated with different content of rGO (about 0, 4, 8, and 12 wt%) were investigated in this study. The electrochemical performance of NVP exhibited a significant enhancement after rGO introduction. The electrode containing about 8 wt% rGO (NVP/G8) showed the best rate and cycle performance. NVP/G8 electrode exhibited the discharge capacity of 64.0 mAh g-1 at 70°C, and achieved high capacity retention of 95.5% after cycling at 10°C for 100 cycles. The polarization of the electrode was inhibited by the introduction of rGO sheets. Meanwhile, compared with the pristine NVP electrode, NVP/G8 electrode exhibited small resistance and high diffusion coefficient of sodium ions.

4.
Asian Pac J Cancer Prev ; 15(8): 3503-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24870747

RESUMO

BACKGROUND: Interleukin-33 (IL-33) has recently been implicated in tumor development. METHODS: Data was obtained from PubMed, EMBASE, Clinical trial, Cochrane Library, Web of Science, CNKI and Wanfang databases. After quality assessment and data extraction, a meta-analysis was performed using Review Manager 5. 2 software. RESULTS: There were eight documents included in this meta-analysis. The results showed IL33 levels to be higher in tumor patients than that in health people, but no correlations tumor stage, metastasis and survival time of tumor patients were evident. CONCLUSION: IL33 may be useful as an alarm factor in tumor detection and prognosis.


Assuntos
Biomarcadores Tumorais/sangue , Interleucinas/sangue , Neoplasias/sangue , Humanos , Interleucina-33
5.
Asian Pac J Cancer Prev ; 15(2): 877-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24568511

RESUMO

OBJECTIVE: To evaluate risk factors for gallstones after gastrectomy. METHODS: To identify documents published from 1990 to 2011 the Pubmed, Cochrane Library, Springer Link, CBM and WanFang databases were searched and a meta-analysis was performed with RevMan 5.2 software for odds ratios and 95%CIs. RESULTS: Fifteen studies were selected for the meta-analysis. The pooled ORs [95%CIs] were 0.56 [0.43, 0.73], (P<0.0001) for digestive tract reconstruction, 0.80 [0.54, 1.17], (P=0.25) for pylorus preservation, 0.33[0.15, 0.75], (P=0.008) for resection scope of stomach, 0.33 [0.15, 0.75], (P=0.008) for lymphadenectomy, and 0.13 [0.05, 0.33], (P<0.0001) for vagotomy. CONCLUSIONS: Digestive tract physical reconstruction and vagus nerve preservation can reduce the morbidity of gallstones after gastrectomy. Total gastrectomy can add to the morbidity of galltones as does increasing the degree of lymph node dissection. There was no significant difference in gallstones with or without pylorus preservation.


Assuntos
Cálculos Biliares/etiologia , Gastrectomia/efeitos adversos , Excisão de Linfonodo/efeitos adversos , Complicações Pós-Operatórias/etiologia , Neoplasias Gástricas/cirurgia , Estudos de Casos e Controles , Humanos , Prognóstico , Fatores de Risco , Neoplasias Gástricas/complicações
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