Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
1.
Plant Dis ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654534

RESUMO

Lily (Lilium spp.) is a valuable ornamental bulb flower plant in Liliaceae, and its bulbs have high edible and medicinal value. Compared with bulb propagation of other lilies, seed propagation and short growth period are the most significant characteristics of Lilium×formolongi. In 2023, leaf rot disease (LRD) was observed on approximately 70% of the Lilium×formolongi seedlings sown in an experimental greenhouse in Wuhan, Hubei province, China. Irregular brown water-soaked spots were discovered in the early stages of infected seedlings. Then, spots spread throughout the leaves and caused the leaves to brown, soften, and wilted. A pathogen associated with symptoms was isolated by incubating sterilized leaves on potato dextrose agar plates at 25 ℃ for 2-3 days. Then, a pure single colony was isolated through a single hyphal tip isolation method. The fungal colony was white with abundant aerial mycelium and produced a yellow pigment diffusible into the agar. Microscopically, isolated mycelia were reticulate and pale yellow, while conidia were dark brown, smooth, and spherical, 7.31 to 6.98 × 4.03 to 3.87µm (average 5.44×5.41µm; n=30); oval in lateral view, and had a light stripe in the middle. To identify the species of the fungus at the molecular level, ITS and EF-1α genes were amplified and sequenced using primers ITS1/ITS4 (M Gardes et al. 1993) and 758F/986R (Carbone and Kohn 1999). The BLAST results in GenBank showed that the ITS(OR523578) and EF-1α(PP066842) sequences of LRD shared 99.82% and 99.24% identity with the distinct Apiospora paraphaeosperma strains (GenBank accession MT040110, ON806628.1, respectively). Combined with the morphology of the colony and conidium, the fungus was identified as Ap. paraphaeosperma. In the pathogenicity test, six healthy leaves were inoculated with mycelium disc and then kept in an incubator (22 ℃, 90% humidity, 16h light /8h darkness). The inoculated leaves showed necrosis and wilt symptoms similar to those observed in the greenhouse, while the control leaves were asymptomatic. A re-isolation, morphology identification and DNA sequencing of the fungus confirmed its infection with Ap. paraphaeosperma in Lilium spp. At present, rot caused by Ap. paraphaeosperma has only been reported in Thailand and South Korea, both of which are found on bamboo stems (Hyde et al. 2016; Sun Lul Kwon et al. 2022). As far as we know, this is the first report of leaf rot of lily caused by Ap. paraphaeosperma in China. This report can help identify this disease and further develop effective control measures.

2.
J Colloid Interface Sci ; 664: 25-32, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458052

RESUMO

Lignin upgrading to various functional products is promising to realize high-value utilization of low-cost and renewable biomass waste, but is still in its infancy. Herein, using industry waste lignosulfonate as the biomass-based carbon source and urea as the dopant, we constructed a heteroatom-doped porous carbon nanosheet structure by a simple NaCl template-assisted pyrolytic strategy. Through the synergistic effect of the NaCl template and urea, the optimized lignin-derived porous carbon catalyst with high content of active nitrogen species and large specific surface area can be obtained. As a result, the fabricated catalysts exhibited excellent electrocatalytic oxygen reduction activity, as well as good methanol tolerance and stability, comparable to that of commercial Pt/C. Moreover, rechargeable Zn-air batteries assembled with this electrocatalyst have a peak power density of up to 150 mW cm-2 and prominent long-term cycling stability. This study offers an inexpensive and efficient way for the massive production of highly active metal-free catalysts from the plentiful, inexpensive and environmentally friendly lignin, offering a good direction for biomass waste recycling and utilization.

3.
J Phys Chem Lett ; 15(13): 3486-3492, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38513132

RESUMO

Atomic-level modulation of the metal-oxide interface is considered an effective approach to optimize the electronic structure and catalytic activity of metal catalysts but remains highly challenging. Here, we employ the atomic layer deposition (ALD) technique together with a heteroatom doping strategy to effectively tailor the electronic metal-support interaction (EMSI) at the metal-oxide interface on the atomic level, thereby achieving high hydrogen evolution performance and Pt utilization. Theoretical calculations reveal that the doping of N atoms in Co3O4 significantly adjusts the EMSI between Pt-Co3O4 interfaces and, consequently, alters the d-band center of Pt and optimizes the adsorption/desorption of reaction intermediates. This work sheds light on the atomic-level regulation and mechanistic understanding of the EMSI in metal-oxide, while providing guidance for the development of advanced EMSI electrocatalysts for various future energy applications.

4.
ACS Appl Mater Interfaces ; 16(7): 8885-8894, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38330505

RESUMO

The solid-state zinc-air batteries have attracted extensive attention due to their high theoretical energy density, high safety, and the compact structure. In this work, a novel hydrogel solid-state electrolyte was developed that was equipped with an interpenetrating network of zinc polyacrylate (PAZn) and polyacrylamide (PAM). At the same time, a cyclodextrin derivative with sulfonate groups was introduced as an additive. From the design of anionic groups in the network, effective and stable channels for zinc species have been established. The unique structure of the additives regulates the uniform deposition of zinc. After using this solid-state electrolyte, the cycle lifetime of solid-state zinc-air batteries assembled have been significantly extended. The byproducts were greatly suppressed and generated the smooth zinc electrode surface after the charge-discharge cycling.

5.
Environ Pollut ; 344: 123347, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215868

RESUMO

The influence of petroleum-based microplastics (MPs) on phytoplankton has been extensively studied, while research on the impact of biodegradable MPs, derived from alternative plastics to contest the environmental crisis, remains limited. This study performed a 63 days co-incubation experiment to assess the effect of polylactic acid MPs (PLA-MPs) on the growth, physiology, and carbon utilization of M. aeruginosa and the change in PLA-MPs surface properties. The results showed that despite PLA-MPs induced oxidative stress and caused membrane damage in M. aeruginosa, the presence of PLA-MPs (10, 50, and 200 mg/L) triggered significant increases (p < 0.05) in the density of M. aeruginosa after 63 days. Specifically, the algal densities upon 50 and 200 mg/L PLA-MPs exposure were increased by 20.91% and 36.31% relative to the control, respectively. Meanhwhile, the reduced C/O ratio on PLA-MPs surface and change in PLA-MPs morphological characterization, which is responsible for substantially increase in the aquatic dissolved inorganic carbon concentration during the co-incubation, implying the degradation of PLA-MPs; thus, provided sufficient carbon resources that M. aeruginosa could assimilate. This was in line with the declined intracellular carbonic anhydrase content in M. aeruginosa. This study is the first attempt to uncover the interaction between PLA-MPs and M. aeruginosa, and the finding that their interaction promotes the degrading of PLA-MPs meanwhile favoring M. aeruginosa growth will help elucidate the potential risk of biodegradable MPs in aquatic environment.


Assuntos
Microcystis , Microplásticos , Microplásticos/toxicidade , Plásticos/toxicidade , Ecossistema , Carbono , Poliésteres/toxicidade
6.
Inorg Chem ; 63(6): 2954-2966, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38288974

RESUMO

Carbon dioxide (CO2) cycloaddition not only produces highly valued cyclic carbonate but also utilizes CO2 as C1 resources with 100% atomic efficiency. However, traditional catalytic routes still suffer from inferior catalytic efficiency and harsh reaction conditions. Developing multienergy-field catalytic technology with expected efficiency offers great opportunity for satisfied yield under mild conditions. Herein, Zn3In2S6 with sulfur vacancies (Sv) was fabricated with the assistance of cetyltrimethylammonium bromide (CTAB), which is further employed for photothermally driven CO2 cycloaddition first. Photoluminescence spectroscopy and photoelectrochemical characterization demonstrated its superior separation kinetics of photoinduced carriers induced by defect engineering. The temperature-programmed desorption (TPD) technique indicated its excellent Lewis acidity-basicity characters. Due to the combination of above merits from photocatalysis and thermal catalysis, defective Zn3In2S6-Sv achieved a yield as high as 73.2% for cyclic carbonate at 80 °C under blue LED illumination within 2 h (apparent quantum yield of 0.468% under illumination of 380 nm monochromatic light at 36 mW·cm-2), which is 2.9, 2.0, and 6.9 times higher than that in dark conditions and those of pristine Zn3In2S6 and industrial representative tetrabutylammonium bromide (TBAB) thermal-catalysis process under the same conditions, respectively. The synergistic reaction path of photocatalysis and thermal catalysis was discriminated by theoretical calculation. This work provides new insights into the photothermal synergistic catalysis CO2 cycloaddition with defective ternary metal sulfides.

7.
Chem Commun (Camb) ; 59(43): 6544-6547, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37161882

RESUMO

Herein, a series of Ru/ZTCs samples were prepared using LaY zeolite-templated carbon as a support. Characterizations showed that the unique structure of the ZTCs and the chemical state of Ru facilitated superior HER performance compared to other carbon-supported samples. This work offers a new strategy for designing excellent electrocatalysts.

8.
Chem Commun (Camb) ; 59(40): 6040-6043, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37185589

RESUMO

Methanol (CH3OH) oxidation offers a promising avenue for transitioning to clean energy, particularly in the field of direct methanol fuel cells (DMFCs). However, the development of efficient and cost-effective catalysts for the methanol oxidation reaction (MOR) remains a critical challenge. Herein, we report the exceptional electrocatalytic activity and stability of Ni3Sn4 toward MOR in acidic media, achieving a performance comparable to that of commercial Pt/C catalysts. Our catalyst design incorporates Earth-abundant Ni and Sn elements, resulting in a material that is 1800 times more cost-effective than Pt/C. Density functional theory (DFT) modeling substantiates our experimental findings, shedding light on the favorable reaction mechanisms and kinetics on the Ni3Sn4 surface. Additionally, the as-synthesized Ni3Sn4 electrocatalyst demonstrates commendable durability, maintaining its electrocatalytic activity even after prolonged exposure to harsh acidic conditions.

9.
J Colloid Interface Sci ; 643: 17-25, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37044010

RESUMO

Using seawater as the replacement of freshwater for electrolysis, with the integration of renewable energy, is deemed as an attractive manner to harvest green hydrogen. However, the complexity of seawater puts forward stricter requirement to the electrocatalyst to alleviate the chlorine electrochemistry and corrosion. Herein, a nanosheet array of NiFe-MOF@Ni2P/Ni(OH)2 is devised by partially substituting terephthalic acid (H2BDC) ligand by ferrocenecarboxylic acid (FcCA). Tailoring the active site into an under-coordinated fashion affords NiFe-MOF@Ni2P/Ni(OH)2 excellent performance towards oxygen evolution reaction (OER), only requiring the overpotentials of 302 mV and 394 mV in alkaline seawater to drive the current densities of 100 and 1000 mA cm-2, respectively. Moreover, the as-obtained electrocatalyst showed robust durability for operating more than 120 h at 500 mA cm-2 under harsh condition (6 M KOH + 1.5 M NaCl, 60 ℃). Density functional theory (DFT) calculations confirmed that tuning the coordination environment of Ni in NiFe-MOF by incorporating the non-bridging FcCA ligands could boost the formation of more active catalytic sites, which can simultaneously enhance the electronic conductivity and accelerate OER kinetics. This work provides beneficial enlightenment of combining MOF-based electrocatalyst with direct electrolysis of seawater.

10.
Langmuir ; 39(10): 3762-3769, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36872656

RESUMO

Simultaneously achieving electrochemical conversion of biomass-derived molecules into value-added products and energy-efficient hydrogen production is a highly attractive strategy but challenging. Herein, we reported a heterostructured Ni/Ni0.2Mo0.8N nanorod array electrocatalyst deposited on nickel foam (Ni/Ni0.2Mo0.8N/NF), which exhibited excellent electrocatalytic activity toward 5-hydroxymethylfurfural (HMF) oxidation, and nearly 100% conversion of HMF and 98.5% yield of 2,5-furandicarboxylic acid (FDCA) products can be achieved. The post-reaction characterizations unveil that Ni species in Ni/Ni0.2Mo0.8N/NF would be readily converted to NiOOH as the real active sites. Furthermore, a two-electrode electrolyzer was assembled with Ni/Ni0.2Mo0.8N/NF utilized as a bifunctional electrocatalyst for both the cathode and anode, giving rise to a low voltage of 1.51 V to concurrently produce FDCA and H2 at 50 mA cm-2. This work enlightens the significance of regulating redox activities of transition metals via interfacial engineering and constructing heterostructured electrocatalysts toward more efficient energy utilization.

11.
Chem Commun (Camb) ; 59(30): 4491-4494, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36974508

RESUMO

We propose a facile and scalable in situ polymerization strategy to selectively introduce the active quinone-based components across the carbon nanotube (CNT) surface. It can be observed that the optimized poly(anthraquinonyl sulfide) (PAQS)/CNT composites exhibit excellent activity and selectivity with a H2O2 yield ratio of approximately 91% at 0.5 V (vs. RHE), together with satisfactory stability at 0.5 V over 20 h. The electrocatalytic performance is correlated with the synergistic effect between PAQS and CNTs. That is, PAQS grafted with abundant quinone groups facilitates the 2 e- ORR process to produce H2O2, and the conductive CNT scaffold is beneficial for the uniform distribution of PAQS and ensures the fast electron transport through the composites.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36981700

RESUMO

In the Yangtze River Delta region, where the agricultural economy is well developed and agricultural pollution and carbon emissions are significant, a regional study of AEE (Agricultural Eco-Efficiency) is crucial to reducing agricultural environmental pollution, improving the rationalization of agricultural production layout, and promoting the realization of low-carbon goals. The SBM-Tobit model and GIS were employed to analyze AEE based on the carbon emission evaluation system in the spatial and temporal characteristics, as well as the influencing factors and the migration path of the center of gravity in the "low carbon" context. A rational plan of agricultural production was proposed according to the results. The following results were obtained: (1) The level of AEE in the Yangtze River Delta region was high, and the region exhibited a U-shaped curve change from 2000 to 2020, with a fluctuating decrease from 2000 to 2003 and a fluctuating increase from 2004 to 2020. The regional spatial development balance was enhanced, while there was a spatial incongruity in the development process of AEE enhancement, high in the southwest and low in the northeast; (2) AEE generally had a high regionalized agglomeration of low-low in the southwest and high-high in the northeast. Nonetheless, temporal heterogeneity was observed in spatial correlation, and the correlation weakened with time variation; (3) Urbanization level, agricultural production structure, crop cultivation structure, and fertilizer application intensity were the main factors influencing AEE in the Yangtze River Delta region; (4) The center of gravity of AEE in the Yangtze River Delta region shifted to the southwest under the influence of "low-carbon" related policies. Therefore, the improvement of AEE in the Yangtze River Delta region should focus on inter-regional coordination and linkages, rational planning of production factors, and the formulation of measures under relevant carbon policies.


Assuntos
Poluição Ambiental , Urbanização , China , Rios , Carbono/análise , Desenvolvimento Econômico , Cidades
13.
Reproduction ; 165(4): 457-474, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36745023

RESUMO

In brief: Impaired spermatogenesis resulting from disturbed cholesterol metabolism due to intake of high-fat diet (HFD) has been widely recognized, however, the role of preprotein invertase subtilin 9 (PCSK9), which is a negative regulator of cholesterol metabolism, has never been reported. This study aims to reveal the role of PCSK9 on spermatogenesis induced by HFD in mice. Abstract: Long-term consumption of a high-fat diet (HFD) is an important factor that leads to impaired spermatogenesis exhibiting poor sperm quantity and quality. However, the mechanism of this is yet to be elucidated. Disrupted cholesterol homeostasis is one of many crucial pathological factors which could contribute to impaired spermatogenesis. As a negative regulator of cholesterol metabolism, preprotein invertase subtilin 9 (PCSK9) mediates low density lipoprotein receptor (LDLR) degradation to the lysosome, thereby reducing the expression of LDLR on the cell membrane and increasing serum low-density lipoprotein cholesterol level, resulting in lipid metabolism disorders. Here, we aim to study whether PCSK9 is a pathological factor for impaired spermatogenesis induced by HFD and the underlying mechanism. To meet the purpose of our study, we utilized wild-type C57BL/6 male mice and PCSK9 knockout mice with same background as experimental subjects and alirocumab, a PCSK9 inhibitor, was used for treatment. Results indicated that HFD induced higher PCSK9 expression in serum, liver, and testes, and serum PCSK9 is negatively correlated with spermatogenesis, while both PCSK9 inhibitor treatment and PCSK9 knockout methodologies ameliorated impaired lipid metabolism and spermatogenesis in mice fed a HFD. This could be due to the overexpression of PCSK9 induced by HFD leading to dyslipidemia, resulting in testicular lipotoxicity, thus activating the Bcl-2-Bax-Caspase3 apoptosis signaling pathway in testes, particularly in Leydig cells. Our study demonstrates that PCSK9 is an important pathological factor in the dysfunction of spermatogenesis in mice induced by HFD. This finding could provide innovative ideas for the diagnosis and treatment of male infertility.


Assuntos
Dieta Hiperlipídica , Pró-Proteína Convertase 9 , Animais , Masculino , Camundongos , beta-Frutofuranosidase , Colesterol , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/genética , Sêmen
14.
Br J Dermatol ; 188(1): 84-93, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689521

RESUMO

BACKGROUND: Keloids represent one extreme of aberrant dermal wound healing and are characterized by fibroblast hyperproliferation and excessive deposition of extracellular matrix. Genetics is a major factor for predisposition to keloids and genome-wide association study has identified a single-nucleotide polymorphism (SNP) rs873549 at 1q41 as a susceptibility locus. The SNP rs873549, and the SNPs in strong linkage disequilibrium (LD) with rs873549, may be involved in keloid development. However, the functional significance of these SNPs in keloid pathogenesis remains elusive. OBJECTIVES: To investigate the function and mechanism of SNP rs873549 and the SNPs in strong LD with rs873549 in keloids. METHODS: SNPs in strong LD with rs873549 were analysed using Haploview. The expression levels of the genes near the susceptibility locus were analysed using quantitative real-time polymerase chain reaction. The interaction between rs1348270-containing enhancer and the long noncoding RNA down expressed in keloids (DEIK) (formerly RP11-400N13.1) promoter in fibroblasts was investigated using chromosome conformation capture. The enhancer activity of the rs1348270 locus was evaluated using luciferase reporter assay. Knockdown experiments were used to explore the function of DEIK in keloids. RNA-Seq was performed to investigate the mechanism by which DEIK regulates the expression of collagens POSTN and COMP. RESULTS: rs1348270, an enhancer-located SNP in strong LD with rs873549, mediated looping with the promoter of DEIK. The risk variant was associated with decreased enhancer-promoter interaction and DEIK down-expression in keloids. Mechanistically, downregulation of DEIK increased the expression of collagens POSTN and COMP through upregulating BMP2. Furthermore, correlation analysis revealed that DEIK expression was inversely correlated with BMP2, POSTN and COMP expression in both keloid and normal fibroblasts. CONCLUSIONS: Our findings suggest that the risk variant rs1348270 is located in an enhancer and is associated with the downregulation of DEIK in keloids, and that downregulation of DEIK increases the expression of collagens POSTN and COMP through BMP2 in keloid fibroblasts. These findings will help to provide a more thorough understanding of the role played by genetic factors in keloid development and may lead to new strategies for screening and therapy in keloid-susceptible populations.


Assuntos
Queloide , RNA Longo não Codificante , Humanos , Queloide/patologia , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/metabolismo , Estudo de Associação Genômica Ampla , Regiões Promotoras Genéticas , Fibroblastos/metabolismo
15.
Life Sci ; 313: 121224, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435224

RESUMO

AIMS: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in the women of childbearing age. It is characterized by hyperandrogenism and abnormal follicular growth and ovulation. The polyol pathway is a glucose metabolism bypass pathway initiated by aldose reductase (ADR). Androgen induces the expression of ADR in the male reproductive tract, which has a general physiological significance for male reproductive function. Here we investigate whether hyperandrogenemia in PCOS leads to increased flux of the polyol pathway in ovarian tissue, which in turn affects follicular maturation and ovulation through oxidative stress. MAIN METHODS: We used clinical epidemiological methods to collect serum and granulosa cells from clinical subjects for a clinical case-control study. At the same time, cell biology and molecular biology techniques were used to conduct animal and cell experiments to further explore the mechanism of hyperandrogen-induced ovarian polyol pathway hyperactivity and damage to ovarian function. KEY FINDINGS: Here, we find that hyperandrogenism of PCOS can induce the expression of ovarian aldose reductase, which leads to the increase of the polyol pathway flux, and affects ovarian function through excessive oxidative stress. SIGNIFICANCE: Our research has enriched the pathological mechanism of PCOS and may provide a new clue for the clinical treatment of PCOS.


Assuntos
Hiperandrogenismo , Síndrome do Ovário Policístico , Humanos , Animais , Feminino , Masculino , Síndrome do Ovário Policístico/metabolismo , Hiperandrogenismo/metabolismo , Aldeído Redutase/metabolismo , Estudos de Casos e Controles , Estresse Oxidativo
16.
Chem Commun (Camb) ; 59(4): 474-477, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36524562

RESUMO

The design and preparation of advanced nanocatalysts for the sensitive electrochemical detection of H2O2 is of great significance. Herein, a facile Pt@Co/MoN sensing platform was fabricated by depositing Pt nanoparticles onto Co/MoN nanoarrays using atomic layer deposition (ALD) technology. Benefitting from the unique nanostructure and the strong interaction between Pt and the nitride support, the prepared Pt@Co/MoN exhibited excellent performance in the electrochemical detection of H2O2. This work provides an interesting strategy to fabricate low-Pt electrocatalysts on a nanoarray support for future applications in electroanalysis.

17.
ACS Appl Mater Interfaces ; 14(39): 44389-44397, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153962

RESUMO

Dielectric capacitors possessing the inherent superiorities of high power density and ultrafast charge-discharge speed make their utilization in energy-storage devices extremely propitious, although the relatively low recoverable energy-storage density (Wrec) may impede their applications. In this work, unlike the mainstream approach of destroying long-range ferroelectric/antiferroelectric order and inducing relaxor properties to achieve a high Wrec value, we have selected end members with a high polarization gene to promote the polarization behavior of the typical relaxor Sr0.7Bi0.2TiO3. Therefore, an ultrahigh Wrec ∼ 8 J/cm3 and a superior efficiency (η) ∼ 91% are accomplished in the 0.98[0.56(Sr0.7Bi0.2)TiO3-0.44(Bi0.5Na0.5)TiO3]-0.02 Bi(Mg0.5Ti0.5)O3 sample. The achieved Wrec value is record high in Sr0.7Bi0.2TiO3-based systems as far as we know. The polarization-enhancement behavior can be explained by the phase field simulation results, phase content variance in X-ray diffraction Rietveld refinement, hardening trend in Raman spectroscopy, domain morphology, and local symmetry in transmission electron microscope analysis. Meanwhile, the ceramic possesses excellent thermal stability (ΔWrec < 12.7% and Δη < 10.4%, -50-200 °C), frequency (ΔWrec < 2.69% and Δη < 2.06%, 0.5-500 Hz), and fatigue-resistant stability (ΔWrec < 0.08% and Δη < 0.2%, up to 1 × 105 cycles). Accordingly, this work proposes a design idea to tailor the polarization behavior and energy-storage properties of typical relaxors.

18.
ACS Appl Mater Interfaces ; 14(19): 22061-22070, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35535851

RESUMO

Developing high-performance non-noble bifunctional catalysts is pivotal for large-scale seawater electrolysis but remains a challenge. Here we report a sandwichlike NiCo(HPO4)2@Ni3N/NF (denoted by NiCoHPi@Ni3N/NF) catalyst. Vertical Ni3N nanosheet arrays are first grown and supported on nickel foam, and then a bimetallic NiCoHPi coating is decorated on Ni3N nanosheets by one-step electrodeposition. The hierarchical sandwich like structure offers a large surface area and plenty of catalytic active sites, and the coupling of interconnected Ni3N and NiCoHPi accelerates the electron transfer. Moreover, the surficial hydrogen phosphate ions contribute to a proper OH- absorption capacity due to the Lewis acid-base reaction. As a result, the NiCoHPi@Ni3N/NF catalyst exhibits good OER and HER activity, requiring overpotentials of 365 mV (for OER) and 174 mV (for HER) to deliver 100 mA cm-2 in the alkaline simulated seawater electrolyte. When assembled the NiCoHPi@Ni3N/NF catalyst as both the anode and cathode, it only needs 1.86 V to reach 100 mA cm-2 in alkaline simulated seawater electrolyte. This work may inspire the design and exploration of self-supported hierarchical composite electrocatalysts for hydrogen production from the electrolysis of seawater.

19.
Reproduction ; 163(5): 293-307, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35275843

RESUMO

Uterine receptivity to the embryo is crucial for successful implantation. The establishment of uterine receptivity requires a large amount of energy, and abnormal energy regulation causes implantation failure. Glucose metabolism in the endometrium is tissue specific. Glucose is largely stored in the form of glycogen, which is the main energy source for the endometrium. AMP-activated protein kinase (AMPK), an important energy-sensing molecule, is a key player in the regulation of glucose metabolism and its regulation is also tissue specific. However, the mechanism of energy regulation in the endometrium for the establishment of uterine receptivity remains to be elucidated. In this study, we aimed to investigate the energy regulation mechanism of mouse uterine receptivity and its significance in embryo implantation. The results showed that the AMPK, p-AMPK, glycogen synthase 1, and glycogen phosphorylase M levels and the glycogen content in mouse endometrial epithelium varied in a periodic manner under regulation by the ovarian hormone. Specifically, progesterone significantly activated AMPK, promoted glycogenolysis, and upregulated glycogen phosphorylase M expression. AMPK regulated glycogen phosphorylase M expression and promoted glycogenolysis. AMPK was also found to be activated by changes in the energy or glycogen of the endometrial epithelial cells. The inhibition of AMPK activity or glycogenolysis altered the uterine receptivity markers during the window of implantation and ultimately interfered with implantation. In summary, consistency and synchronization of AMPK and glycogen metabolism constitute the core regulatory mechanism in mouse endometrial epithelial cells involved in the establishment of uterine receptivity.


Assuntos
Proteínas Quinases Ativadas por AMP , Glicogênio , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Implantação do Embrião/fisiologia , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Glicogênio/metabolismo , Camundongos
20.
Small Methods ; 6(4): e2101470, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35212473

RESUMO

Large scale solar-driven hydrogen production is a crucial step toward decarbonizing society. However, the solar-to-hydrogen (STH) conversion efficiency, long-term stability, and cost-effectiveness in hydrogen evolution reaction (HER) still need to be improved. Herein, an efficient approach is demonstrated to produce low-dimensional Pt/graphene-carbon nanofibers (CNFs)-based heterostructures for bias-free, highly efficient, and durable HER. Carbon dots are used as efficient building blocks for the in situ formation of graphene along the CNFs surface. The presence of graphene enhances the electronic conductivity of CNFs to ≈3013.5 S m-1  and simultaneously supports the uniform Pt clusters growth and efficient electron transport during HER. The electrode with a low Pt loading amount (3.4 µg cm-2 ) exhibits a remarkable mass activity of HER in both acidic and alkaline media, which is significantly better than that of commercial Pt/C (31 µg cm-2  of Pt loading). In addition, using a luminescent solar concentrator-coupled solar cell to provide voltage, the bias-free water splitting system exhibits an STH efficiency of 0.22% upon one-sun illumination. These results are promising toward using low-dimensional heterostructured catalysts for future energy storage and conversion applications.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA