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1.
Genome Res ; 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35868641

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-38776264

RESUMO

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.
Molecules ; 29(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542904

RESUMO

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.


Assuntos
Antioxidantes , Panax , Humanos , Antioxidantes/química , Lactobacillus/metabolismo , Fermentação , Extratos Vegetais/farmacologia , Panax/química
4.
Metab Brain Dis ; 36(7): 1763-1777, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34417940

RESUMO

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.


Assuntos
Medicamentos de Ervas Chinesas , Glycyrrhiza , Transtornos de Estresse Pós-Traumáticos , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Farmacologia em Rede , Qualidade de Vida , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico
5.
BMC Public Health ; 16: 123, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26850629

RESUMO

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.


Assuntos
Fontes de Energia Elétrica , Doenças Profissionais/epidemiologia , Estresse Psicológico/epidemiologia , Trabalho/psicologia , Adaptação Psicológica , Adulto , China/epidemiologia , Estudos Transversais , Tomada de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Doenças Profissionais/psicologia , Recompensa , Apoio Social , Estresse Psicológico/psicologia , Avaliação da Capacidade de Trabalho
6.
Zhongguo Zhong Yao Za Zhi ; 40(2): 298-302, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-26080562

RESUMO

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.


Assuntos
Indutores da Angiogênese/farmacologia , Isquemia Encefálica/patologia , Movimento Celular/efeitos dos fármacos , Ventrículos Cerebrais/patologia , Medicamentos de Ervas Chinesas/farmacologia , Neurônios/efeitos dos fármacos , Animais , Isquemia Encefálica/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/genética , Quimiocina CXCL12/análise , Quimiocina CXCL12/genética , Proteína Duplacortina , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurônios/fisiologia
7.
Nutr Cancer ; 66(7): 1165-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25256273

RESUMO

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.


Assuntos
Comportamento Alimentar , Neoplasias da Glândula Tireoide/epidemiologia , Animais , Bases de Dados Factuais , Grão Comestível , Frutas , Humanos , Incidência , Iodo/administração & dosagem , Iodo/análise , Iodo/deficiência , Carne , Estudos Observacionais como Assunto , Razão de Chances , Fatores de Risco , Alimentos Marinhos , Verduras
8.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(3): 342-7, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24758088

RESUMO

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.


Assuntos
Isquemia Encefálica/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Neurogênese/efeitos dos fármacos , Animais , Isquemia Encefálica/tratamento farmacológico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Masculino , Fitoterapia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
J Colloid Interface Sci ; 666: 416-423, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603883

RESUMO

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.

10.
J Colloid Interface Sci ; 660: 97-105, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241875

RESUMO

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.

11.
Nanotechnology ; 24(4): 045609, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23299661

RESUMO

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.


Assuntos
Aminas/química , Coloides/química , Cristalização/métodos , Grafite/química , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
12.
J Phys Chem Lett ; 14(49): 11177-11182, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38055448

RESUMO

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.

13.
J Colloid Interface Sci ; 646: 597-605, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37210907

RESUMO

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.

14.
Nat Prod Res ; 37(15): 2602-2607, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35337222

RESUMO

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.


Assuntos
Nozes , Pinus , Nozes/química , Óleos de Plantas/química , Pinus/química , Água/química , Antioxidantes/química
15.
Nanomaterials (Basel) ; 13(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37630905

RESUMO

The electrocatalytic conversion of biomass into high-value-added chemicals is one of the effective methods of green chemistry. Conventional metal catalysts have disadvantages, such as low atomic utilization and small surface areas. Catalyst materials derived from metal-organic frameworks (MOFs) have received much attention due to their unique physicochemical properties. Here, an MOF-derived non-precious metal CoxNiyS electrocatalyst was applied to the oxidation of biomass-derivative 5-hydroxymethylfurfural (HMF). The HMF oxidation reaction activities were modulated by regulating the content of Co and Ni bimetals, showing a volcano curve with an increasing proportion of Co. When the Co:Ni ratio was 2:1, the HMF conversion rate reached 84.5%, and the yield of the main product, 2,5-furandicarboxylic acid (FDCA), was 54%. The XPS results showed that the presence of high-valent nickel species after electrolysis, which further proved the existence and reactivity of NiOOH, as well as the synergistic effect of Co and Ni promoted the conversion of HMF. Increasing the content of Ni could increase the activity of HMF electrochemical oxidation, and increasing the content of Co could reduce the increase in the anodic current. This study has important significance for designing better HMF electrochemical catalysts in the future.

16.
J Colloid Interface Sci ; 650(Pt A): 446-455, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418895

RESUMO

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.

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

RESUMO

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.
Food Chem ; 422: 136224, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37137239

RESUMO

To avoid wasting blueberry pomace resources, deep eutectic solvents (DESs) were combined with ultrasound technology to establish an efficient green method for the recovery of anthocyanins and polyphenols from plant-derived by-products. Choline chloride:1,4-butanediol (molar ratio of 1:3) was chosen as the optimal solvent based on the screening of eight solvents and single-factor experiments. Response surface methodology was applied to optimize the extraction parameters: water content, 29%; extraction temperature, 63 °C; liquid-solid ratio, 36:1 (v/w). The yields of total anthocyanins and total polyphenols from the optimized extraction were 11.40 ± 0.14 mg cyanidin-3-glucoside equiv./g and 41.56 ± 0.17 mg gallic acid equiv./g, respectively, which were both significantly better than the yields achieved with 70% ethanol. The purified anthocyanins showed excellent inhibition of α-glucosidase (IC50 = 16.57 µg/mL). The physicochemical parameters of DES suggest that it can be used for the extraction of bioactive substances.


Assuntos
Mirtilos Azuis (Planta) , Polifenóis , Solventes/química , Antocianinas , Mirtilos Azuis (Planta)/química , Solventes Eutéticos Profundos , Extratos Vegetais/química , Etanol
19.
Dalton Trans ; 52(44): 16519-16524, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37877818

RESUMO

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.
J Colloid Interface Sci ; 633: 598-607, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36470139

RESUMO

In this study, we demonstrated the synthesis of potassium chloride (KCl)-incorporated graphitic carbon nitride, (g-C3N4, CN) with varying amounts of N-vacancies and pyridinic-N as well as enhanced Lewis basicity, via a single-step thermal polymerization by tailoring the precursors of melamine and urea for carbon oxide (CO2) capture. Melamine, as a precursor, undergoes a phase transformation into melam and triazine-rich g-C3N4, whereas the addition of urea polymerizes the mixture to form melem and heptazine-rich g-C3N4 (CN11). Owing to the abundance of pyridinic-N and the high surface area, CN11 adsorbed higher amounts of CO2 (44.52 µmol m-2 at 25 °C and 1 bar of CO2) than those reported for other template-free carbon materials. Spectroscopic analysis revealed that the enhanced CO2 adsorption is due to the presence of pyridinic-N and Lewis basic sites on the surface. The intermediates of CO2adsorption, including carbonate and bicarbonate species, attached to the CN samples were identified using in-situ Fourier-transform infrared spectroscopy (FTIR). This work provides insights into the mechanism of CO2 adsorption by comparing the structural features of the synthesized KCl-incorporated g-C3N4 samples. CN11, with an excellent CO2 uptake capacity, is viewed as a promising candidate for CO2 capture and storage.


Assuntos
Dióxido de Carbono , Ureia , Cloreto de Potássio , Dióxido de Carbono/química , Adsorção , Ureia/química , Triazinas/química
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