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1.
Genome Res ; 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35868641

RESUMEN

Histone modifications are critical epigenetic indicators of chromatin state associated with gene expression. Although the reprogramming patterns of H3K4me3 and H3K27me3 have been elucidated in mouse and human preimplantation embryos, the relationship between these marks and zygotic genome activation (ZGA) remains poorly understood. By ultra-low-input native chromatin immunoprecipitation and sequencing, we profiled global H3K4me3 and H3K27me3 in porcine oocytes and in vitro fertilized (IVF) embryos. We found that promoters of ZGA genes occupied sharp H3K4me3 peaks in oocytes, and these peaks became broader after fertilization, and reshaped into sharp again during ZGA. By simultaneous depletion of H3K4me3 demethylase KDM5B and KDM5C, we determined that broad H3K4me3 domain maintenance impaired ZGA gene expression, suggesting its function to prevent premature ZGA entry. By contrast, broad H3K27me3 domains underwent global removal upon fertilization, followed by a re-establishment for H3K4me3/H3K27me3 bivalency in morulae. We also found that bivalent marks were deposited at promoters of ZGA genes, and inhibiting this deposition was correlated with the activation of ZGA genes. It suggests that promoter bivalency contributes to ZGA exit in porcine embryos. Moreover, we demonstrated that aberrant reprogramming of H3K4me3 and H3K27me3 triggered ZGA dysregulation in somatic cell nuclear transfer (SCNT) embryos, whereas H3K27me3-mediated imprinting did not exist in porcine IVF and SCNT embryos. Our findings highlight two previously unknown epigenetic reprogramming modes coordinated with ZGA in porcine preimplantation embryos. Finally, the similarities observed between porcine and human histone modification dynamics suggest that the porcine embryo may also be a useful model for human embryo research.

2.
Nano Lett ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38776264

RESUMEN

High-entropy-alloy nanoparticles (HEA NPs) exhibit promising potential in various catalytic applications, yet a robust synthesis strategy has been elusive. Here, we introduce a straightforward and universal method, involving the microexplosion of Leidenfrost droplets housing carbon black and metal salt precursors, to fabricate PtRhPdIrRu HEA NPs with a size of ∼2.3 nm. The accumulated pressure within the Leidenfrost droplet triggers an intense explosion within milliseconds, propelling the carbon support and metal salt rapidly into the hot solvent through explosive force. The exceptionally quick temperature rise ensures the coreduction of metal salts, and the dilute local concentration of metal ions limits the final size of the HEA NPs. Additionally, the explosion process can be fine-tuned by selecting different solvents, enabling the harvesting of diverse HEA NPs with superior electrocatalytic activity for alcohol electrooxidation and hydrogen electrocatalysis compared to commercial Pt (Pd) unitary catalysts.

3.
Inorg Chem ; 63(40): 18855-18864, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39325016

RESUMEN

In this paper, heterogeneous cobalt phosphosulfide (Co4S3/Co2P) nanocrystals anchoring on few-layered MXene nanosheets (MXene@Co4S3/Co2P) were prepared by in situ growth and the subsequent high-temperature phosphorization/sulfidation processes. Thanks to the synergistic effect and the abundant phase interfaces of Co4S3, Co2P, and MXene, the electron transfer and Na+ diffusion processes were greatly accelerated. Meanwhile, the high electrical conductivity of MXene nanosheets and the heterogeneous structure of Co4S3/Co2P effectively avoided the MXene restacking and the agglomeration of phosphosulfide particles, thus mitigating volumetric expansion during charging and discharging. The results show that the MXene@Co4S3/Co2P heterostructure presents good rate capability (251.08 mAh g-1 at 1 A g-1) and excellent cycling stability (198.69 mAh g-1 after 407 cycles at 5 A g-1). Finally, the storage mechanism of Na+ in the heterostructure and the multistep phase transition reaction were determined by ex situ X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS) analyses. This study provides a new perspective on the formation of metal phosphosulfide and MXene hybrids with multiple heterointerfaces as well as demonstrates MXene@Co4S3/Co2P composites as the promising anode material in sodium-ion batteries.

4.
Molecules ; 29(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38542904

RESUMEN

Ginseng holds high medicinal and cosmetic value, with stem and leaf extracts garnering attention for their abundant bioactive ingredients. Meanwhile, fermentation can enhance the effectiveness of cosmetics. The aim of this study was to optimize ginseng fermentation to produce functional cosmetics. Ginseng stem and leaf extracts were fermented with five different strains of lactic acid bacteria. Using 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical (·OH), and superoxide anion (O2·-) scavenging activities as indicators, the fermentation process was optimized via response surface methodology. Finally, validation of the antioxidant activity of the optimized fermentation broth was performed using human skin cells (HaCaT and BJ cells). Based on the antioxidant potency composite comprehensive index, Lactiplantibacillus plantarum 1.140 was selected, and the optimized parameters were a fermentation time of 35.50 h, an inoculum size of 2.45%, and a temperature of 28.20 °C. Optimized fermentation boosted antioxidant activity: DPPH scavenging activity increased by 25.00%, ·OH by 94.00%, and O2·- by 73.00%. Only the rare ginsenoside Rg5 showed a substantial rise in content among the 11 ginsenosides examined after fermentation. Furthermore, the flavonoid content and ·OH scavenging activity were significantly negatively correlated (r = -1.00, p < 0.05), while the Rh1 content and O2·- scavenging activity were significantly positively correlated (r = 0.998, p < 0.05). Both the 0.06% (v/v) and 0.25% (v/v) concentrations of the optimized broth significantly promoted cell proliferation, and notable protective effects against oxidative damage were observed in HaCaT cells when the broth was at 0.06%. Collectively, we demonstrated that ginseng fermentation extract effectively eliminates free radicals, preventing and repairing cellular oxidative damage. This study has identified new options for the use of fermented ginseng in functional cosmetics.


Asunto(s)
Antioxidantes , Panax , Humanos , Antioxidantes/química , Lactobacillus/metabolismo , Fermentación , Extractos Vegetales/farmacología , Panax/química
5.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3706-3713, 2024 Jul.
Artículo en Zh | MEDLINE | ID: mdl-39099345

RESUMEN

Acupoint drug delivery is a traditional external therapy of traditional Chinese medicine(TCM). Guided by the meridian and collateral theory in TCM, it applies medications to the skin at acupoints, exerting a dual therapeutic effect by stimulating the acupoints and the conduction of meridians. Acupoint drug delivery is widely used in clinical practice. Different from traditional oral admi-nistration and injection, it absorbs medications through the skin, effectively avoiding the first-pass effect of drugs and the toxic side effects caused by injection. Acupoint selection and transdermal drug absorption are pivotal factors affecting the efficacy of acupoint drug delivery. Recent research on acupoint drug delivery mainly focuses on the evaluation of clinical efficacy, yet the systematic investigations on acupoint selection and pharmacodynamic factors are scarce. This study reviews the mechanism, efficacy evaluation and application status of acupoint drug delivery. It integrates the theory of TCM with modern medicine to explore the mechanism of acupoint drug delivery, evaluate its clinical efficacy, and assess the transdermal penetration in vivo and in vitro. The application status of acupoint drug delivery is also summarized, including the selection of acupoints, application dosage form, application time and the absorption of acupoints. This review aims to offer insights and references for the research, development and clinical application of acupoint drug delivery products.


Asunto(s)
Puntos de Acupuntura , Sistemas de Liberación de Medicamentos , Humanos , Sistemas de Liberación de Medicamentos/métodos , Animales , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacocinética , Absorción Cutánea/efectos de los fármacos , Meridianos , Medicina Tradicional China , Administración Cutánea
6.
Metab Brain Dis ; 36(7): 1763-1777, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34417940

RESUMEN

Post traumatic stress disorder (PTSD) is a mental health condition that has a debilitating effect on a person's quality of life and leads to a high socioeconomic burden. Licorice has been demonstrated to have neuroprotective and antidepressant-like effects, but little is known about its effects for the treatment of PTSD. The present study aimed to explore the potential of licorice for PTSD therapy using a network pharmacology approach with molecular docking studies. The compounds of licorice were obtained from databases with screening by absorption, distribution, metabolism and excretion (ADME) evaluation. Genes associated with compounds or PTSD were obtained from public databases, and the genes overlapping between licorice compounds and PTSD were compared by Venn diagram. A network of medicine-ingredients-targets-disease was constructed, visualized, and analyzed using cytoscape software. Protein-protein interactions, gene ontology, pathway enrichment and molecular docking were performed to evaluate the effect of licorice for the treatment of PTSD. 69 potential compounds were screened after ADME evaluation. A total of 81 compound-related genes and 566 PTSD-related genes were identified in the databases with 27 overlapping genes. Licorice compounds (e.g., medicarpin, 7-methoxy-2-methyl isoflavone, shinpterocarpin, formononetin, licochalcone a) and target proteins (e.g., ESR1, PTGS2, NOS2, and ADRB2) with high degree in the network were involved in G protein-coupled receptor signaling pathways at the postsynaptic/synaptic membrane. Moreover, neuroactive ligand-receptor interactions, calcium signaling, cholinergic synapse, serotonergic synapse and adrenergic signaling in cardiomyocytes may play important roles in the treatment of PTSD by licorice. This study provides molecular evidence of the beneficial effects of licorice for the treatment of PTSD.


Asunto(s)
Medicamentos Herbarios Chinos , Glycyrrhiza , Trastornos por Estrés Postraumático , Medicamentos Herbarios Chinos/farmacología , Humanos , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Farmacología en Red , Calidad de Vida , Trastornos por Estrés Postraumático/tratamiento farmacológico
7.
BMC Public Health ; 16: 123, 2016 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-26850629

RESUMEN

BACKGROUND: Faced with the challenge of population aging, a prolonged working life is increasingly important in today's society. Maintaining work ability of employees is one of the effective ways to cope with the challenges to sustainability of the workforce presented by population aging. Researchers have shown ongoing interest in exploring the determinants of restricted work ability. The aim of this study was to evaluate the effects of work stress on work ability among power supply workers in Guangdong, China. METHODS: A cross-sectional study was conducted among power supply workers during August 2014 to September 2014. A total of 805 subjects were enrolled in the study. Work stress was assessed by the Job Content Questionnaire and the Effort Reward Imbalance Questionnaire. Work ability was assessed by the Work Ability Index (WAI). The structural equation model was applied to test the relationship between different work stress components and work ability simultaneously using the Job Demands-Resources model as a framework. RESULTS: Job resources (measured by job control, reward and social support) were positively and directly associated with work ability (ß = 0.70, P < 0.001). The association between job demands and work ability was also statistically significant (ß = -0.09, P = 0.030). In addition, the findings also supported previous studies in that job demands were correlated with job resources (ß = -0.26, P < 0.001). CONCLUSIONS: Our findings suggest that decision makers and health care providers should consider increasing job resources available to power supply workers. Consideration of organizational changes related to the design of the job task also would be useful to improve the employees' work ability.


Asunto(s)
Suministros de Energía Eléctrica , Enfermedades Profesionales/epidemiología , Estrés Psicológico/epidemiología , Trabajo/psicología , Adaptación Psicológica , Adulto , China/epidemiología , Estudios Transversales , Toma de Decisiones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Enfermedades Profesionales/psicología , Recompensa , Apoyo Social , Estrés Psicológico/psicología , Evaluación de Capacidad de Trabajo
8.
Zhongguo Zhong Yao Za Zhi ; 40(2): 298-302, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-26080562

RESUMEN

OBJECTIVE: To study the effect of Buyang Huanwu decoction (BYHWD) inducing angiogenesis on the neuroblast migration from the subventricular zone and its mechanisms after focal cerebral ischemia. METHOD: The middle cerebral artery occlusion (MCAO) was performed to mice for 30 minutes to establish the model. The rats were divided into sham group, model group, BYHWD group and endostatin group. BYHWD (20 g x kg(-1), ig) and endostatin (10 µg, sc) were administered 24 h after ischemia once a day for consecutively 14 days. At 14 d after ischemia, the density of micro-vessel and the number of neuroblasts in the ischemia border zone were determined by immunofluorescence staining. The mRNA and protein expression of cell-derived factor-1 (SDF-1) and brain-derived neurotrophic (BDNF) were examined by real-time PCR and Western blot. RESULT: Compared with the model group, BYHWD significantly increased the density of micro-vessel and the number of DCX positive cells in the ischemia border zone (P < 0.01), and significantly increased the SDF-1 and BDNF mRNA and protein expression (P < 0.01). Compared with BYHWD group, endostatin significantly reduced the density of micro-vessel and the number of DCX positive cells in the ischemia border zone (P < 0.01), as well as the SDF-1, BDNF mRNA and protein expression (P < 0.01). CONCLUSION: BYHWD could promote the neuroblast migration from the subventricular zone via inducing angiogenesis after cerebral ischemia, the mechanism may be correlated with up-regulating the expression of SDF-1 and BDNF.


Asunto(s)
Inductores de la Angiogénesis/farmacología , Isquemia Encefálica/patología , Movimiento Celular/efectos de los fármacos , Ventrículos Cerebrales/patología , Medicamentos Herbarios Chinos/farmacología , Neuronas/efectos de los fármacos , Animales , Isquemia Encefálica/fisiopatología , Factor Neurotrófico Derivado del Encéfalo/análisis , Factor Neurotrófico Derivado del Encéfalo/genética , Quimiocina CXCL12/análisis , Quimiocina CXCL12/genética , Proteína Doblecortina , Masculino , Ratones , Ratones Endogámicos ICR , Neuronas/fisiología
9.
Nutr Cancer ; 66(7): 1165-78, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25256273

RESUMEN

To better understand the relationship between dietary factors and thyroid cancer risk, we summarized the published evidence on relationship between dietary factors and thyroid cancer incidence. Searching several databases for relevant studies published by March 2014 included a total of 19 studies. We calculated summary odds ratios (ORs) for each risk factor. Based on the highest level of total consumption vs. the lowest level, the summary OR [95% (confidence interval) CI] of thyroid cancer was 0.79 (0.66, 0.94) for fish; 0.95 (0.74, 1.23) for salt water fish; 0.86 (0.63, 1.16) for fresh water fish; 0.76 (0.58, 1.00) for vegetables; 0.88 (0.72, 1.08) for shellfish; 0.93 (0.66, 1.29) for cruciferous vegetables; 0.97 (0.78, 1.21) for fruits; 0.96 (0.70, 1.34) for meat; and 1.11 (0.86, 1.42) for grains. Subgroup analysis showed that fish (OR 0.74, 95%CI: 0.59, 0.92) and shellfish (OR 0.46, 95%CI: 0.27, 0.75) consumption have a protective effect in iodine deficiency areas, whereas the ORs were not statistically significant in iodine-rich areas. Our findings indicated that fish and shellfish consumption may decrease the risk of thyroid cancer in iodine deficiency areas, although no such effect was observed in iodine-rich areas.


Asunto(s)
Conducta Alimentaria , Neoplasias de la Tiroides/epidemiología , Animales , Bases de Datos Factuales , Grano Comestible , Frutas , Humanos , Incidencia , Yodo/administración & dosificación , Yodo/análisis , Yodo/deficiencia , Carne , Estudios Observacionales como Asunto , Oportunidad Relativa , Factores de Riesgo , Alimentos Marinos , Verduras
10.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(3): 342-7, 2014 Mar.
Artículo en Zh | MEDLINE | ID: mdl-24758088

RESUMEN

OBJECTIVE: To explore the effect of Buyang Huanwu Decoction (BYHWD) and its disassembled recipes on rats' neurogenesis after focal cerebral ischemia and to investigate its underlying molecular mechanisms. METHODS: Focal cerebral ischemia model was induced by occlusion of the right middle cerebral artery for 90 min using the intraluminal filament model. Rats were divided into the sham-operation group, the model group, the BYHWD group, the qi supplementing group, and the blood activating group. Medication was performed by gastrogavage 24 h after ischemia for 14 successive days. 5-bromodeoxyuridine (BrdU) (at 50 mg/kg) was intraperitoneally injected, once per day for 14 successive days. The neurological function was assessed using modified neurological severity score (mNSS) and the corner test at day 1, 7, and 14 after ischemia. BrdU/Nestin, BrdU/NeuN, and BrdU/GFAP positive cells were examined by double immunofluorescence at day 14 after ischemia. The protein expression of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) were detected by Western blot at day 14 after ischemia. RESULTS: Compared with the model group, the score of mNSS and the frequency of turning right significantly decreased in the BYHWD group and the qi supplementing group (P < 0.01), the number of BrdU/Nestin in the subventricular zone of the lateral ventricle, and BrdU/ NeuN and BrdU/GFAP positive cells in the peripheral ischemic cortex increased (P < 0.05, P < 0.01), protein expression of BDNF and VEGF increased (P < 0.05, P < 0.01). In the qi supplementing group, there was no statistical difference in BrdU/GFAP. But there was no statistical difference in each index of the blood activating group (P > 0.05). Compared with BYHWD group, the number of BrdU/Nestin, BrdU/ NeuN, and BrdU/GFAP positive cells significantly decreased (P < 0.01), and the protein expression of BDNF and VEGF were significantly reduced in the qi supplementing group and the blood activating group (P < 0.01). CONCLUSIONS: BYHWD could significantly improve neurogenesis and neurological function recovery after focal cerebral ischemia in rats. Its mechanisms might be related to up-regulating protein expression of BDNF and VEGF. Drugs for qi supplementing and drugs for blood activating had synergistic effects.


Asunto(s)
Isquemia Encefálica/metabolismo , Medicamentos Herbarios Chinos/farmacología , Neurogénesis/efectos de los fármacos , Animales , Isquemia Encefálica/tratamiento farmacológico , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Medicamentos Herbarios Chinos/uso terapéutico , Masculino , Fitoterapia , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/metabolismo
11.
J Colloid Interface Sci ; 666: 416-423, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38603883

RESUMEN

The construction of heterostructure materials has been demonstrated as the promising approach to design high-performance anode materials for sodium ion batteries (SIBs). Herein, micro-mesoporous cobalt phosphosulfide nanowires (Co3S4/CoP/NC) with Co3S4/CoP hetero-nanocrystals encapsulating into N-doped carbon frameworks were successfully synthesized via hydrothermal reaction and subsequent phosphosulfidation process. The obtained micro-mesoporous nanowires greatly improve the charge transport kinetics from the facilitation of the charge transport into the inner part of nanowire. When evaluated as SIBs anode material, the Co3S4/CoP/NC presents outstanding electrochemical performance and battery properties owing to the synergistic effect between Co3S4 and CoP nanocrystals and the conductive carbon frameworks. The electrode material delivers outstanding reversible rate capacity (722.33 mAh/g at 0.1 A/g) and excellent cycle stability with 522.22 mAh/g after 570 cycles at 5.0 A/g. Besides, the Ex-situ characterizations including XRD, XPS, and EIS further revealed and demonstrated the outstanding sodium ion storage mechanism of Co3S4/CoP/NC electrode. These findings pave a promising way for the development of novel metal phosphosulfide anodes with unexpected performance for SIBs and other alkali ion batteries.

12.
J Colloid Interface Sci ; 660: 97-105, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38241875

RESUMEN

Synthesis of advanced structure and multiple heteroatom-doped carbon based heterostructure materials are the key to the preparation of high-performance energy storage electrode materials. Herein, the hexapod-shaped Co1-xS@NPSC has been triumphantly prepared using hexapod ZIF-67 as the sacrificial template to prepare Co1-xS inner core and N, P, and S tri-doped carbon (NPSC) as the shell through the carbonization of the organic polymer precursor. When applied as anode for Na+ batteries (SIBs) and K+ batteries (PIBs), Co1-xS@NPSC presents the high reversible specific capability of 747.4 mAh/g at 1.0 A/g after 235 cycles and 387.8 mAh/g at 5.0 A/g after 760 cycles for SIBs, as well as 326.7 mAh/g at 1.0 A/g after 180 cycles for PIBs. The excellent storage capacity and rate capability of Co1-xS@NPSC is ascribed to hexapod structure of ZIF-67 unlike the common dodecahedron, which is constructed with interior porous and exterior framework repository, donating supplemental active sites, and doping of multiple heteroatoms forming organic polymer coating inhibiting the volume expansion and restrains the agglomeration of Co1-xS nanoparticles. This approach has paved a bright avenue to exploit promising anode materials with novel structure and hetero-atom doping for high-performance energy storage devices.

13.
Mater Today Bio ; 27: 101153, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39081462

RESUMEN

The advantage of low-temperature forming through direct ink writing (DIW) 3D printing is becoming a strategy for the construction of innovative drug delivery systems (DDSs). Optimization of the complex formulation, including factors such as the printing ink, presence of solvents, and potential low mechanical strength, are challenges during process development. This study presents an application of DIW to fabricate water-soluble, high-dose, and sustained-release DDSs. Utilizing poorly compressible metformin hydrochloride as a model drug, a core-shell delivery system was developed, featuring a core composed of 96 % drug powder and 4 % binder, with a shell structure serving as a drug-release barrier. This design aligns with the sustained-release profile of traditional processes, achieving a 25.8 % reduction in volume and enhanced mechanical strength. The strategy facilitates sustained release of high-dose water-soluble formulations for over 12 h, potentially improving patient compliance by reducing formulation size. Process optimization and multi-batch flexibility were also explored in this study. Our findings provide a valuable reference for the development of innovative DDSs and 3D-printed drugs.

14.
Nanotechnology ; 24(4): 045609, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23299661

RESUMEN

An eco-friendly, facile and scalable hydrothermal approach, in which the reduction and functionalization of graphite oxide (GO) are completed in one pot, is proposed for the synthesis of monolayer 3-aminopropyltriethoxysilane (APTES)-functionalized graphenes (A-FGs). Atomic force microscopy, transmission electron microscopy and x-ray diffraction analyses indicate that the as-synthesized A-FGs consist of only one or a few layered graphenes, while x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis reveal that APTES is bonded to graphene by the dehydration reaction between the Si-OH (produced by APTES hydration) and the -OH on the GO surface. As a result, free amino groups are left on the A-FGs. Moreover, A-FGs are highly dispersible in dimethylsulfoxide, APTES and ethylene glycol, and their solubilities are up to 0.89, 4.03 and 0.90 mg ml(-1), respectively.


Asunto(s)
Aminas/química , Coloides/química , Cristalización/métodos , Grafito/química , Membranas Artificiales , Nanoestructuras/química , Nanoestructuras/ultraestructura , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
15.
J Phys Chem Lett ; 14(49): 11177-11182, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38055448

RESUMEN

Direct ethanol fuel cells show great promise as a means of converting biomass ethanol derived from biomass into electricity. However, the efficiency of complete conversion is hindered by the low selectivity in breaking the C-C bond. This selectivity is determined by factors such as the material structure and reaction conditions, including the nature of the supporting electrolyte. Cations serve not only as facilitators of electricity conduction through ion migration but also as influencers of the reaction pathways. In this study, we utilized differential electrochemical mass spectrometry to track the in situ generation of CO2 during potential scanning. The presence of alkali cations led to an enhancement in the CO2 selectivity. In addition, in situ Raman spectroscopy provided evidence of the formation of alkali metal cation-sulfate anion ion pairs. The catalytic activity and CO2 selectivity were found to be directly correlated to the ionic strength of these ion pairs.

16.
J Colloid Interface Sci ; 646: 597-605, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37210907

RESUMEN

Herein, selenium (Se)-doped MoS1.5Se0.5@VS2 nanosheets aggregated nano-roses were successfully prepared from a simple hydrothermal process and the subsequent selenium doping process. The hetero-interfaces between MoS1.5Se0.5 and VS2 phase can effectively promote the charge transfer. Meanwhile, the different redox potentials of MoS1.5Se0.5 and VS2 alleviate volume expansion during the repeated sodiation/desodiation processes, which improves the electrochemical reaction kinetics and structural stability of electrode material. Besides, Se doping can induce charge reconstruction and improve the conductivity of electrode materials, resulting in improved diffusion reaction kinetics by expanding interlayer spacing and exposing more active sites. When used as anode material for sodium ion batteries (SIBs), the MoS1.5Se0.5@VS2 heterostructure exhibits excellent rate capability and long-term cycling stability with the capacity of 533.9 mAh g-1 at 0.5 A g-1 and a reversible capacity of 424.5 mAh g-1 after 1000 cycles at 5 A g-1, demonstrating potential application as anode material for SIBs.

17.
J Colloid Interface Sci ; 650(Pt A): 132-142, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37399749

RESUMEN

Converting CO2 into valuable chemicals and fuels through clean and renewable energy electricity provides a way to achieve sustainable development for human societies. In this study, carbon coated nickel catalysts (Ni@NCT) were prepared by solvothermal and high-temperature pyrolysis methods. A series of Ni@NC-X catalysts were obtained by pickling with different kinds of acids for electrochemical CO2 reduction reaction (ECRR). The results show that Ni@NC-N treated with nitric acid has the highest selectivity but lower activity, Ni@NC-S treated with sulfuric acid has the lowest selectivity, and Ni@NC-Cl treated with hydrochloric acid shows the best activity and good selectivity. At -1.16 V, Ni@NC-Cl has a considerable CO yield of 472.9 µmol h-1 cm-2, which is significantly superior to Ni@NC-N (327.5), Ni@NC-S (295.6) and Ni@NC (270.8). The controlled experiments show that there is a synergistic effect between Ni and N. The chlorine adsorbed on the surface can promote the performance of ECRR. The poisoning experiments indicate that the contribution of surface Ni atoms to the ECRR is very small, and the increase of activity is mainly due to the nitrogen doped carbon coated Ni particles. The relationship between activity and selectivity of ECRR on different acid-washed catalysts was correlated by theoretical calculations for the first time, which is also in good agreement with the experimental results.

18.
J Colloid Interface Sci ; 650(Pt A): 446-455, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37418895

RESUMEN

Herein, heterogeneous bimetallic sulfides Bi2S3/Mo7S8 nanoparticles anchored on MXene (Ti3C2Tx) nanosheets (MXene@Bi2S3/Mo7S8) were prepared through a solvothermal process and subsequent chemical vapor deposition process. Benefiting from the heterogeneous structure between Bi2S3 and Mo7S8 and the high conductivity of the Ti3C2Tx nanosheets, the Na+ diffusion barrier and charge transfer resistance of this electrode are effectively decreased. Simultaneously, the hierarchical architectures of Bi2S3/Mo7S8 and Ti3C2Tx not only effectively inhibit the re-stacking of MXene and the agglomeration of bimetallic sulfides nanoparticles, but also dramatically relieve the volume expansion during the periodic charge/discharge processes. As a result, the MXene@Bi2S3/Mo7S8 heterostructure demonstrated remarkable rate capability (474.9 mAh/g at 5.0 A/g) and outstanding cycling stability (427.3 mAh/g after 1400 cycles at 1.0 A/g) for sodium ion battery. The Na+ storage mechanism and the multiple-step phase transition in the heterostructures are further clarified by the ex-situ XRD and XPS characterizations. This study paves a new way to design and exploit conversion/alloying type anodes of sodium ion batteries with hierarchical heterogeneous architecture and high-performance electrochemical properties.

19.
Dalton Trans ; 52(44): 16519-16524, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37877818

RESUMEN

In this paper, a cobalt-based sulfide nanosheet structure (Co9S8/NC) was successfully synthesized by topochemical and phase transformation processes from a dodecahedral cobalt-based imidazole skeleton (ZIF-67) as a self-template. The 2D sheet structure facilitates full contact of electrode materials with the electrolyte and shortens the diffusion distance for electrons and ions. In addition, the nitrogen-doped carbon framework derived from ZIF-67 promotes electron transfer and provides a reliable skeleton to buffer volume expansion during discharging and charging. Finally, Co9S8/NC exhibits excellent rate capability and stable cycling performance for the anode of a sodium ion battery, delivering a specific capacity remaining at 530 mA h g-1 after 130 cycles at a current density of 1 A g-1.

20.
Nat Prod Res ; 37(15): 2602-2607, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35337222

RESUMEN

Response surfaces methodology was established in order to optimize ultrasound-assisted aqueous alkaline protease extraction parameters of Pinus koraiensis nuts oil (PNO) in this short communication. On the oil yield, the impacts of single factors were studied. The solid-liquid ratio, enzyme concentration, enzyme hydrolysis temperature, and enzyme hydrolysis duration were chosen for further optimization of the extraction process utilizing a Box-Behnken design based on statistical significance analysis. Under ideal extraction conditions, a maximum oil recovery of 68.35% was achieved: solid-liquid ratio, enzyme concentration, enzyme hydrolysis temperature, and enzyme hydrolysis duration were 1:5 (g/mL), 3.23 mg/g, 44 °C, and 2.84 h, respectively. Furthermore, physicochemical properties testing revealed that the oil was of higher quality than other approaches. Meanwhile, the DPPH radical-scavenging activities increased with increased content compared to olive oil, with an IC50 value of 0.082 mg/mL. The method has a lot of potential when it comes to extracting oils from plants.


Asunto(s)
Nueces , Pinus , Nueces/química , Aceites de Plantas/química , Pinus/química , Agua/química , Antioxidantes/química
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