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1.
Crit Rev Food Sci Nutr ; : 1-13, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38835159

RESUMEN

The global rise in life expectancy corresponds with a delay in childbearing age among women. Ovaries, seen as the chronometers of female physiological aging, demonstrate features of sped up aging, evidenced by the steady decline in both the quality and quantity of ovarian follicles from birth. The multifaceted pathogenesis of ovarian aging has kindled intensive research interest from the biomedical and pharmaceutical sectors. Novel studies underscore the integral roles of gut microbiota in follicular development, lipid metabolism, and hormonal regulation, forging a nexus with ovarian aging. In this review, we outline the role of gut microbiota in ovarian function (follicular development, oocyte maturation, and ovulation), compile and present gut microbiota alterations associated with age-related ovarian aging. We also discuss potential strategies for alleviating ovarian aging from the perspective of gut microbiota, such as fecal microbiota transplantation and probiotics.

2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 348-353, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-38864299

RESUMEN

Objective To investigate the relationship between cerebrovascular reactivity (CVR) and emotional disorders in the patients undergoing continuous hemodialysis for end-stage renal disease (ESRD).Methods The clinical data of the ESRD patients undergoing continuous hemodialysis were collected.Anxiety and depression of the patients were assessed by the Hamilton anxiety scale (HAMA) and Beck depression inventory,respectively.The cerebral hemodynamic changes during the breath holding test were monitored by transcranial Doppler sonography,and the breath-holding index (BHI) was calculated.The BHI≥0.69 and BHI<0.69 indicate normal CVR and abnormal CVR,respectively.Binary Logistic regression was employed to analyze the factors affecting the depressive state of ESRD patients.Results The group with abnormal CVR exhibited higher total cholesterol level (P=0.010),low density lipoprotein level (P=0.006),and incidence of depression (P=0.012) than the group with normal CVR.Compared with the non-depression group,the depression group displayed prolonged disease course (P=0.039),reduced body mass index (P=0.048),elevated HAMA score (P=0.001),increased incidence of anxiety (P<0.001),decreased BHI (P=0.015),and increased incidence of abnormal CVR (P=0.012).Binary Logistic regression analysis indicated anxiety as a contributing factor (OR=22.915,95%CI=2.653-197.956,P=0.004) and abnormal CVR as a risk factor (OR=0.074,95%CI=0.008-0.730,P=0.026) for depression.Conclusion Impaired CVR could pose a risk for depression in the patients with ESRD.


Asunto(s)
Depresión , Fallo Renal Crónico , Humanos , Masculino , Femenino , Persona de Mediana Edad , Fallo Renal Crónico/fisiopatología , Fallo Renal Crónico/complicaciones , Depresión/fisiopatología , Adulto , Diálisis Renal , Circulación Cerebrovascular/fisiología , Anciano
3.
Angew Chem Int Ed Engl ; : e202402371, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38763920

RESUMEN

2D compounds exfoliated from weakly bonded bulk materials with van der Waals (vdW) interaction are easily accessible. However, the strong internal ionic/covalent bonding of most inorganic crystal frameworks greatly hinders 2D material exfoliation. Herein, we first proposed a radical/strain-synergistic strategy to exfoliate non-vdW interacting pseudo-layered phosphate framework. Specifically, hydroxyl radicals (⋅OH) distort the covalent bond irreversibly, meanwhile, H2O molecules as solvents, further accelerating interlayered ionic bond breakage but mechanical expansion. The innovative 2D laminar NASICON-type Na3V2(PO4)2O2F crystal, exfoliated by ⋅OH/H2O synergistic strategy, exhibits enhanced sodium-ion storage capacity, high-rate performance (85.7 mAh g-1 at 20 C), cyclic life (2300 cycles), and ion migration rates, compared with the bulk framework. Importantly, this chemical/physical dual driving technique realized the effective exfoliation for strongly coupled pseudo-layered frameworks, which accelerates 2D functional material development.

4.
Molecules ; 28(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37446928

RESUMEN

Formononetin (FNT) is a plant-derived isoflavone natural product with anti-inflammatory, antioxidant, and anti-allergic properties. We showed previously that FNT inhibits immunoglobulin E (IgE)-dependent mast cell (MC) activation, but the effect of FNT on IgE-independent MC activation is yet unknown. Our aim was to investigate the effects and possible mechanisms of action of FNT on IgE-independent MC activation and pseudoallergic inflammation. We studied the effects of FNT on MC degranulation in vitro with a cell culture model using compound C48/80 to stimulate either mouse bone marrow-derived mast cells (BMMCs) or RBL-2H3 cells. We subsequently measured ß-hexosaminase and histamine release, the expression of inflammatory factors, cell morphological changes, and changes in NF-κB signaling. We also studied the effects of FNT in several in vivo murine models of allergic reaction: C48/80-mediated passive cutaneous anaphylaxis (PCA), active systemic anaphylaxis (ASA), and 2,4-dinitrobenzene (DNCB)-induced atopic dermatitis (AD). The results showed that FNT inhibited IgE-independent degranulation of MCs, evaluated by a decrease in the release of ß-hexosaminase and histamine and a decreased expression of inflammatory factors. Additionally, FNT reduced cytomorphological elongation and F-actin reorganization and attenuated NF-κB p65 phosphorylation and NF-κB-dependent promoter activity. Moreover, the administration of FNT alleviated pseudoallergic responses in vivo in mouse models of C48/80-stimulated PCA and ASA, and DNCB-induced AD. In conclusion, we suggest that FNT may be a novel anti-allergic drug with great potential to alleviate pseudoallergic responses via the inhibition of IgE-independent MC degranulation and NF-κB signaling.


Asunto(s)
Anafilaxia , Antialérgicos , Isoflavonas , Ratones , Animales , Mastocitos , p-Metoxi-N-metilfenetilamina/farmacología , FN-kappa B/metabolismo , Degranulación de la Célula , Dinitroclorobenceno/metabolismo , Anafilaxia/tratamiento farmacológico , Isoflavonas/metabolismo , Inmunoglobulina E/metabolismo , Antialérgicos/uso terapéutico
5.
Phys Chem Chem Phys ; 21(32): 17846-17851, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31378794

RESUMEN

Co-crystallization of organic molecules is an important strategy for the fabrication of molecular materials. In this contribution, we investigated the mixing behavior of 5-(benzyloxy)-isophthalic acid homologues (BIC-Cn, n = 6, 8, 10, 12, and 14) at the liquid/solid interface using a scanning tunneling microscope. Deposition of the single component of BIC-Cn always results in typical honeycomb networks, whereas co-deposition of two BIC-Cn homologues leads to hybrid double-walled honeycomb networks or phase separation depending on the difference in the length of their alkyl chains. 2D co-crystallization can only be realized for BIC-C6/BIC-C10 or BIC-C8/BIC-C12 which have a four-methyl unit difference in their alkyl chains. The size complementarity of the alkyl chains in the two components suggests that it is responsible for the 2D co-crystallization, though hydrogen bonding contributes a lot both to the pristine honeycomb network and to the hybrid co-crystal. This result is of importance for understanding the role of van der Waals interaction and its interplay with hydrogen bonding in 2D co-crystallization.

6.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2736-2741, 2019 Jul.
Artículo en Zh | MEDLINE | ID: mdl-31359684

RESUMEN

Astragali Radix( AR) polysaccharide for injection( Guoyao Zhunzi Z20040086) is a traditional Chinese medicine for intravenous powder injection developed by Shanxi Academy of Traditional Chinese Medicine in early 1990 s by taking advantage of AR resources in Shanxi province. The effective parts of AR polysaccharides were obtained by advanced technology. The hemogram of patients with radiotherapy and chemotherapy showed alleviations in clinic. However,due to the technical bottleneck in separation of the complex polysaccharides mixture and the difficulties in accurate measurement of the polysaccharide structures,the pharmacodynamic mechanism of the drug remained unclear,and the side effect was hard to control. In recent years,the theoretical studies for polysaccharide receptors have indicated that when polysaccharides bound to protein receptors,only the oligosaccharide fragments of the polysaccharide molecule bound to the receptors,and one or more active sites of oligosaccharide fragments may existed in the polysaccharide molecule.Therefore,the active center of polysaccharides can be studied based on the level of oligosaccharides through degradation of the polysaccharides,which provided a new strategy for breaking through the bottleneck in polysaccharide structure determination. Therefore,this paper reviews the current status of studies for AR polysaccharides for injection,the polysaccharide receptors theory and successful cases,in order to propose the secondary development ideas of AR polysaccharides for injection. The study results will lay a material foundation for the development of new drugs of polysaccharides from traditional Chinese medicine,and provide a basis for the resolution of international difficulties in quality control of polysaccharide drugs and molecular models,so as to further study of glycobiology,and enrich the polysaccharide receptors theory.


Asunto(s)
Planta del Astrágalo/química , Medicamentos Herbarios Chinos , Raíces de Plantas/química , Polisacáridos/farmacología , Humanos , Medicina Tradicional China
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(6): 937-940, 2017 Nov.
Artículo en Zh | MEDLINE | ID: mdl-29260534

RESUMEN

OBJECTIVE: To investigate the risk factors for increased red blood cells (RBCs) transfusion ratio in the women with postpartum hemorrhage (PPH). METHODS: This case-control study obtained the inpatient medical records of 112 441 pregnant women from 37 hospitals in 2011. There were 4 131 women diagnosed with PPH,record data of those patients were analyzed,including basic characteristics of patients,the level of hospital,pregnancy related complications,prenatal hemoglobin (Hb),mode of delivery,details of postpartum blood loss and blood transfusion,and maternal and neonatal outcomes. Multiple logistic regression analysis was used to identify risk factors for increased RBCs transfusion ratio. RESULTS: There were 61 339 (54.6%) out of 112 441 women received with Cesarean section and 637 (15.4%) out of 4 131 women with PPH had blood transfusion,one to four units of RBCs were sufficient for a majority of those patients. It demonstrated that level of hospital,multiple,placenta preiva,abruptio placenta,pre-eclampsia or eclampsia,pre-delivery hemoglobin,gestational age and labor method were independent risk factors for RBCs transfusion. CONCLUSION: Cesarean section and pregnant complications are important risk factors for blood transfusion in women with PPH .


Asunto(s)
Transfusión Sanguínea , Cesárea/efectos adversos , Hemorragia Posparto/terapia , Complicaciones del Embarazo/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Factores de Riesgo
8.
Langmuir ; 32(27): 6830-5, 2016 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-27287273

RESUMEN

Spontaneous resolution of enantiomers is an intriguing and important phenomenon in surface chirality studies. Herein, we report on a two-dimensional (2D) structural transition from the heterochiral to homochiral assembly tuned by changing the enantiomeric excess (ee) of enantiomers in the solution phase. Enantiomers cocrystallize as racemates on the surface when the ee of the R-enantiomer (or S-enantiomer) remains below a critical value, whereas chiral segregation is achieved, and globally homochiral surfaces composed of exclusively one enantiomer are obtained as the critical ee is exceeded. The heterochiral-homochiral transition is ascribed to the formation of energetically unfavored homochiral molecular dimers under the control of the majority-rules principle at high ee values. Such results present an intriguing phenomenon in chiral ordering at surfaces, promising a new enlightenment toward understanding chiral resolution and the evolution of chirality.

9.
Phys Chem Chem Phys ; 18(26): 17356-9, 2016 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-27314983

RESUMEN

A bilayer covalent organic framework (COF) of TTF-based building blocks was obtained by imine reaction between tetrathiafulvalene tetraaldehyde (4ATTF) and p-phenylenediamine (PPDA). Direct evidence for the eclipsed stacking of bilayer structure via π-π interaction between TTF units is provided by high resolution scanning tunneling microscopy.

10.
Community Ment Health J ; 52(4): 493-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26993652

RESUMEN

The aims of this study were to examine the relationships between overall cognitive function and the quality of life (QOL) domains, and to compare the differences in these by age, gender, and educational level in community-dwelling seniors in Taiwan. A cross-sectional study was conducted, with the participants screened and recruited from Southern Tainan. The Saint Louis University Mental Status Examination was used to screen the cognitive status of the participants. A total of 144 seniors participated in this study were assessed using the Taiwanese version of WHOQOL-BREF. The results showed that the participants performed better in the cognitive domains of "figure identification" and "orientation" while they performed poor in "delayed recall" and "immediate paragraph recall". No significant relationship between cognitive function and overall QOL, but a positive relationship between cognitive function and the physical health domain of QOL was found. The findings of this study provide valuable information for community healthcare providers.


Asunto(s)
Cognición , Disfunción Cognitiva/psicología , Calidad de Vida/psicología , Factores de Edad , Anciano , Escolaridad , Femenino , Humanos , Vida Independiente/psicología , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores Sexuales , Encuestas y Cuestionarios , Taiwán/epidemiología
11.
Angew Chem Int Ed Engl ; 55(40): 12393-7, 2016 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-27576570

RESUMEN

A series of self-complementary ureido pyrimidinedione (UPy) derivatives modified with different aurophilic anchoring groups were synthesized. Their electron transport properties through the quadruple hydrogen bonds in apolar solvent were probed employing the scanning tunneling microscopy break junction (STMBJ) technique. The molecule terminated with a thiol shows the optimal electron transport properties, with a statistical conductance value that approaches 10(-3)  G0 . The (1) H NMR spectra and control experiments verify the formation of quadruple hydrogen bonds, which can be effectively modulated by the polarity of the solvent environment. These findings provide a new design strategy for supramolecular circuit elements in molecular electronics.

12.
Inflamm Res ; 64(3-4): 253-60, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25721616

RESUMEN

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is a counter-regulator against ACE by converting angiotensin II (Ang-II) to Ang-(1-7), but the effect of ACE2 and Ang-(1-7) on endothelial cell function and atherosclerotic evolution is unknown. We hypothesized that ACE2 overexpression and Ang-(1-7) may protect endothelial cell function by counterregulation of angiotensin II signaling and inhibition of inflammatory response. METHODS: We used a recombinant adenovirus vector to locally overexpress ACE2 gene (Ad-ACE2) in human endothelial cells in vitro and in apoE-deficient mice in vivo. The Ang II-induced MCP-1, VCAM-1 and E-selectin expression, endothelial cell migration and adhesion of human monocytic cells (U-937) to HUVECs by ACE2 gene transfer were evaluated in vitro. Accelerated atherosclerosis was studied in vivo, and atherosclerosis was induced in apoE-deficient mice which were divided randomly into four groups that received respectively a ACE2 gene transfer, Ad-ACE2, Ad-EGFP, Ad-ACE2 + A779, an Ang-(1-7) receptor antagonist, control group. After a gene transfer for 4 weeks, atherosclerotic pathology was evaluated. RESULTS: ACE2 gene transfer not only promoted HUVECs migration, inhibited adhesion of monocyte to HUVECs and decreased Ang II-induced MCP-1, VCAM-1 and E-selectin protein production in vitro, but also decreased the level of MCP-1, VCAM-1 and interleukin 6 and inhibit atherosclerotic plaque evolution in vivo. Further, administration of A779 increased the level of MCP-1, VCAM-1 and interleukin 6 in vivo and led to further advancements in atherosclerotic extent. CONCLUSIONS: ACE2 and Ang-(1-7) significantly inhibit early atherosclerotic lesion formation via protection of endothelial function and inhibition of inflammatory response.


Asunto(s)
Angiotensina II/fisiología , Angiotensina I/fisiología , Aterosclerosis/prevención & control , Endotelio Vascular/fisiología , Inflamación/prevención & control , Fragmentos de Péptidos/fisiología , Peptidil-Dipeptidasa A/fisiología , Transducción de Señal/fisiología , Angiotensina I/genética , Enzima Convertidora de Angiotensina 2 , Animales , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/fisiopatología , Adhesión Celular/fisiología , Movimiento Celular/fisiología , Quimiocina CCL2/fisiología , Modelos Animales de Enfermedad , Selectina E/fisiología , Endotelio Vascular/citología , Técnicas de Transferencia de Gen , Humanos , Técnicas In Vitro , Inflamación/fisiopatología , Ratones , Fragmentos de Péptidos/genética , Peptidil-Dipeptidasa A/genética , Molécula 1 de Adhesión Celular Vascular/fisiología
13.
Acta Pharmacol Sin ; 36(2): 200-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25619391

RESUMEN

AIM: To investigate the effects of liraglutide, a glucagon-like peptide-1 (GLP-1) receptor activator, on body weight and waist circumference in Chinese overweight and obese type 2 diabetic patients. METHODS: A total of 328 Chinese overweight and obese type 2 diabetic patients were included in this multi-center, open-labeled and self-controlled clinical study. The patients were subcutaneously injected with liraglutide once daily for 24 weeks as add-on therapy to their previous hypoglycemic treatments. Statistical analyses were performed using SPSS software package version 11.5 for Windows. RESULTS: Liraglutide treatment caused significant reduction of the mean body weight (from 86.61±14.09 to 79.10±13.55 kg) and waist circumference (from 101.81±13.96 to 94.29±14.17 cm), resulting in body weight lose of 5%-10% in 43.67% patients, and body weight loss above 10% in 34.06% patients, who had significant lower plasma creatinine levels. Baseline waist circumference, BMI and HOMA-IR were independently correlated with the body weight loss. Furthermore, liraglutide treatment significantly decreased HbA1c levels (from 8.66%±2.17% to 6.92%±0.95%) with HbA1c<7.0% in 35.37% patients, who had a significantly lower baseline level of HbA1c, but higher baseline levels of C peptide and glucagon. Moreover, liraglutide treatment resulted in greater body weight loss in patients with a long duration of diabetes, and better glycemic control in patients with a short duration of diabetes. CONCLUSION: Liraglutide significantly reduces body weight and waist circumference in Chinese overweight and obese type 2 diabetic patients. Patients with apparent visceral obesity, insulin resistance and a long duration of diabetes may have greater body weight loss; whereas patients with high insulin-secreting ability, hyperglucagonemia, and short-duration diabetes may obtain better glycemic control with liraglutide.


Asunto(s)
Peso Corporal/efectos de los fármacos , Diabetes Mellitus Tipo 2/fisiopatología , Péptido 1 Similar al Glucagón/análogos & derivados , Hipoglucemiantes/uso terapéutico , Sobrepeso/tratamiento farmacológico , Circunferencia de la Cintura/efectos de los fármacos , Pueblo Asiatico , Femenino , Péptido 1 Similar al Glucagón/uso terapéutico , Humanos , Liraglutida , Masculino , Persona de Mediana Edad
16.
Forensic Sci Med Pathol ; 11(2): 208-15, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25877518

RESUMEN

We report on a novel application of real-time reverse transcription-loop-mediated isothermal amplification (real-time RT-LAMP) to identify the presence of a specific body fluid using blood as a proof-of-concept model. By comparison with recently developed methods of body fluid identification, the RT-LAMP assay is rapid and requires only one simple heating-block maintained at a single temperature, circumventing the need for dedicated equipment. RNA was extracted from different body fluids (blood, semen, saliva, menstrual blood, sweat, and urine) for use in real-time RT-LAMP reaction. The 18S rRNA locus was used as the internal control and hemoglobin beta (HBB) as the blood-specific marker. Reverse transcription and LAMP reaction were performed in the same tube using a turbidimeter for real-time monitoring the reaction products within a threshold of 60 min. HBB LAMP products were only detected in blood and not in any of the other body fluid, but products from the 18S rRNA gene were detected in all the tested body fluids as expected. The limit of detection was a minimum of 10(-5) ng total RNA for detection of both 18S rRNA and HBB. Augmenting the detection of RT-LAMP products was performed by separation of the products using gel electrophoresis and collecting the fluorescence of calcein. The data collected indicated complete concordance with the body fluid tested regardless of the method of detection used. This is the first application of real-time RT-LAMP to detect body fluid specific RNA and indicates the use of this method in forensic biology.


Asunto(s)
Análisis Químico de la Sangre , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN/genética , Saliva/química , Semen/química , Sudor/química , Orina/química , Adulto , Biomarcadores/sangre , Electroforesis en Gel de Agar , Femenino , Fluorescencia , Medicina Legal , Humanos , Masculino , ARN Ribosómico 18S/genética , Reproducibilidad de los Resultados , Adulto Joven , Globinas beta/genética
17.
Angew Chem Int Ed Engl ; 54(14): 4309-14, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25677120

RESUMEN

Remote chiral communication in 2D supramolecular assembly at a liquid/solid interface was investigated at the molecular level. The stereochemical information in a chiral coadsorber was transmitted over a flexible spacer with a length of up to five methylene groups to a 2D supramolecular assembly of achiral building blocks with the cooperation of specific hydrogen bonding between the chiral coadsorber and achiral building blocks and the confinement effect during 2D crystallization. When the position of the stereogenic center was changed with respect to the stereocontrolling moiety, an odd-even effect was found. A stereogenic center closer to the stereocontrolling moiety transmitted the stereochemical information to the 2D supramolecular assembly more reliably. This result is beneficial not only for mechanistic understanding of chiral communication in 2D supramolecular assembly on surfaces but also for the rational design of homochiral supramolecular assemblies on surfaces.


Asunto(s)
Estructura Molecular , Adsorción , Estereoisomerismo , Propiedades de Superficie
18.
Neuroreport ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973496

RESUMEN

The aim of this study was to explore the neuroprotective effects of the P2X7 receptor antagonist A740003 on retinal ganglion cells (RGCs) in chronic intraocular hypertension (COH) experimental glaucoma mouse model. Bioinformatics was used to analyze the glaucoma-related genes. Western blot, real-time fluorescence quantitative PCR, and immunofluorescence staining techniques were employed to explore the mechanisms underlying the neuroprotective effects of A740003 on RGCs in COH retinas. Bioinformatic analysis revealed that oxidative stress, neuroinflammation, and cell apoptosis were highly related to the pathogenesis of glaucoma. In COH retinas, intraocular pressure elevation significantly increased the levels of translocator protein, a marker of microglial activation, which could be reversed by intravitreal preinjection of A740003. A740003 also suppressed the increased mRNA levels of proinflammatory cytokines interleukin (IL) 1ß and tumor necrosis factor α in COH retinas. In addition, although the mRNA levels of anti-inflammatory cytokine IL-4 and IL-10 were kept unchanged in COH retinas, administration of A740003 could increase their levels. The mRNA and protein levels of Bax and cleaved caspase-3 were increased in COH retinas, which could be partially reversed by A740003, while the levels of Bcl-2 kept unchanged in COH retinas with or without the injections of A740003. Furthermore, A740003 partially attenuated the reduction in the numbers of Brn-3a-positive RGCs in COH mice. A740003 could provide neuroprotective roles on RGCs by inhibiting the microglia activation, attenuating the retinal inflammatory response, reducing the apoptosis of RGCs, and enhancing the survival of RGCs in COH experimental glaucoma.

19.
J Colloid Interface Sci ; 664: 381-388, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38479274

RESUMEN

Na3MnTi(PO4)3 (NMTP) emerges as a promising cathode material with high-performance for sodium-ion batteries (SIBs). Nevertheless, its development has been limited by several challenges, including poor electronic conductivity, the Mn3+ Jahn-Teller effect, and the presence of a Na+/Mn2+ cation mixture. To address these issues, we have developed a cation/anion-dual regulation strategy to activate the redox reactions involving manganese, thereby significantly enhancing the performance of NMTP. This strategy simultaneously enhances the structural dynamics and facilitates rapid ion transport at high rates by inducing the formation of sodium vacancy. The combined effects of these modifications lead to a substantial improvement in specific capacity (79.1 mAh/g), outstanding high-rate capabilities (35.9 mAh/g at 10C), and an ultralong cycle life (only 0.040 % capacity attenuation per cycle over 250 cycles at 1C for Na3.34Mn1.2Ti0.8(PO3.98F0.02)3) when used as a cathode material in SIBs. Furthermore, its performance in full cell demonstrates impressive rate capability (44.4 mAh/g at 5C) and exceptional cycling stability (with only 0.116 % capacity decay per cycle after 150 cycles at 1C), suggesting its potential for practical applications. This work presents a dual regulation strategy targeting different sites, offering a significant advancement in the development of NASICON phosphate cathodes for SIBs.

20.
J Colloid Interface Sci ; 670: 174-181, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38761570

RESUMEN

Interlayer intercalation engineering shows great feasibility to improve the structure stability of the layered oxides. Although high Zn-storage capability has been attained based on the pillar effect of multifarious intercalants, an in-depth understanding the synergistic effect of intercalated multiple metal ions is still in deficiency. Herein, alkali metal ion K+, alkaline earth metal ion Mg2+ and trivalent metal ion Al3+ are introduced into the VO interlayer of V2O5. Due to the different electronegativity and hydrated ion radius of K+, Mg2+ and Al3+, adjusting the relative proportions of these metal ions can achieve an appropriate interlayer spacing, stable layer structure and regular morphology, which facilitates the transport kinetics of Zn2+. Under the synergistic effect of pre-intercalated multi-metal ion, the optimal tri-metal ion intercalated hydrated V2O5 cathode exhibits a high specific capacity of 382.4 mAh g-1 at 0.5 A g-1, and long-term cycling stability with capacity retention of 86 % after 2000 cycles at the high current density of 10 A g-1. Ex-situ and kinetic characterizations reveal the fast charge transfer and reversible Zn2+ intercalation mechanism. The multi-ion engineering strategy provides an effective way to design desirable layered cathode materials for aqueous zinc-ion batteries.

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