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1.
3D Print Addit Manuf ; 11(3): e1213-e1226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39359588

RESUMO

Boron-based aids are commonly introduced to tackle the unsatisfactory densification of SS316L parts fabricated by binder jetting (BJ) technology. However, there is scarce study on the effect of sintering aids on the mechanical performance. This work investigates the effect of B4C aids and sintering temperature on the mechanical performance and microscopic morphology of BJ printing SS316L parts. SS316L powders with a bimodal size distribution were adopted to enhance density and reduce the shape distortion. Besides, B4C was added as a sintering aid to promote densification during sintering. The results show that the bimodal powder is in favour of the density increase and the sintering process. The sintering temperature is largely reduced with the addition of B4C. Further, the mechanical performance is mainly affected by the final density and B4C content. In view of a comprehensive evaluation of shape retention and properties, B4C content of 1 wt.% and sintering temperature of 1250°C are expected to be the optimal parameters.

2.
Plant Physiol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39268876

RESUMO

Soybean [Glycine max (L.) Merr.] is a major oil-producing crop worldwide. Although several related proteins regulating soybean oil accumulation have been reported, little is known about the regulatory mechanisms. In this study, we characterized vascular plant one-zinc-finger 1A (GmVOZ1A) that interacts with WRINKLED 1a (GmWRI1a) using yeast two-hybrid library screening. The GmVOZ1A-GmWRI1a interaction was further verified by protein-protein interaction assays in vivo and in vitro. GmVOZ1A enhanced the seed fatty acid and oil contents by regulating genes involved in lipid biosynthesis. Conversely, a loss-of-function mutation in GmVOZ1A resulted in a reduction in triacylglycerol (TAG) content in soybean. Protein-DNA interaction assays revealed that GmVOZ1A and GmWRI1a cooperate to up-regulate the expression level of acyl-coenzymeA-binding protein 6a (GmACBP6a) and promote the accumulation of TAG. In addition, GmACBP6a overexpression promoted seed fatty acid and oil contents, as well as increased seed size and 100-seed weight. Taken together, these findings indicate that the transcription factor GmVOZ1A regulates soybean oil synthesis and cooperates with GmWRI1a to up-regulate GmACBP6a expression and oil biosynthesis in soybean. The results lay a foundation for a comprehensive understanding of the regulatory mechanisms underlying soybean oil biosynthesis and will contribute to improving soybean oil production through molecular breeding approaches.

3.
Heart Fail Rev ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39269643

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome with various phenotypes, and obesity is one of the most common and clinically relevant phenotypes of HFpEF. Obesity contributes to HFpEF through multiple mechanisms, including sodium retention, neurohormonal dysregulation, altered energy substrate metabolism, expansion of visceral adipose tissue, and low-grade systemic inflammation. Glucagon-like peptide-1 (GLP-1) is a hormone in the incretin family. It is produced by specialized cells called neuroendocrine L cells located in the distal ileum and colon. GLP-1 reduces blood glucose levels by promoting glucose-dependent insulin secretion from pancreatic ß cells, suppressing glucagon release from pancreatic α cells, and blocking hepatic gluconeogenesis. Recent evidence suggests that GLP-1 receptor agonists (GLP-1 RAs) can significantly improve physical activity limitations and exercise capacity in obese patients with HFpEF. The possible cardioprotective mechanisms of GLP-1 RAs include reducing epicardial fat tissue thickness, preventing activation of the renin-angiotensin-aldosterone system, improving myocardial energy metabolism, reducing systemic inflammation and cardiac oxidative stress, and delaying the progression of atherosclerosis. This review examines the impact of obesity on the underlying mechanisms of HFpEF, summarizes the trial data on cardiovascular outcomes of GLP-1 RAs in patients with type 2 diabetes mellitus, and highlights the potential cardioprotective mechanisms of GLP-1 RAs to give a pathophysiological and clinical rationale for using GLP-1 RAs in obese HFpEF patients.

4.
Food Chem ; 463(Pt 2): 141133, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39265302

RESUMO

A new convenient method for identifying colorant compounds (CCs) in food matrices was developed using high-performance liquid chromatography with a diode array detector and quadrupole-time-of-flight mass spectrometer (HPLC-DAD-Q/TOF-MS) combined with theoretical calculations. A model sample containing three typical CCs was completely separated via HPLC-DAD. The obtained 3D ultraviolet-visible (UV-vis) spectra revealed the maximum absorption wavelengths (MAWs) of all CCs (yellow, 430 nm; red, 520 nm; blue, 620 nm) in the range of 400-800 nm, and their colors were determined based on their MAWs. Temporary structures of the CCs were obtained using Q/TOF-MS analysis. Theoretical calculations were then performed to obtain the theoretical MAWs and colors of the CCs according to their calculated UV-vis spectra based on temporary structures. The structures of the CCs were confirmed without the need for authoritative standards by comparing the consistency between their experimental and theoretical MAWs and colors. This method is particularly suitable for identifying CCs or compounds with UV-Vis absorption, including new compounds, compounds for which standards are difficult to obtain, and known compounds without reporting relevant molecular information.

5.
Sci Rep ; 14(1): 20830, 2024 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242673

RESUMO

The adverse pregnancy outcomes, including recurrent spontaneous abortion (RSA), are strongly correlated with water-soluble vitamins, but how to predict RSA occurrence using them remains unsatisfactory. This study aims to investigate the possibility of predicting RSA based on the baseline levels of water-soluble vitamins tested by ultra-liquid chromatography-tandem mass spectrometry. A total of 918 pregnant women was consecutively enrolled in this cross-sectional study. According to the miscarriage numbers, they were divided into normal first pregnancy (NFP, n = 608), once spontaneous abortion (OSA, n = 167), and continuous spontaneous abortion (CSA, n = 143) groups. The Cox proportional-hazards regression model was employed to establish a risk model for predicting RSA. The RSA occurrence was 6.54% in overall pregnant women, with a prevalence of 12.57% in the OSA group and 27.27% in the CSA group. Significant differences were observed in baseline deficiencies of vitamin B3, B5, B6, and B9 among NFP, OSA, and CSA groups (χ2 = 12.191 ~ 37.561, all P < 0.001). Among these vitamins, B9 (HR = 0.89 and 0.88, all P < 0.001) and B6 (HR = 0.83 and 0.78, all P < 0.05) were identified as independent factors in both the OSA and CSA groups; whereas B5 was identified as an additional independent factor only in the CSA group (HR = 0.93, P = 0.005). The Cox proportional-hazards model established using these three vitamins exhibited poor or satisfactory predictive performance in the OSA (Sen = 95.2%, Spe = 39.0%) and CSA (Sen = 92.3%, Spe = 60.6%) groups, respectively. However, B5, B6, and B9 compensatory levels were not associated with RSA occurrence (all P > 0.05). Our study presents a highly sensitive model based on mass spectrometry assay of baseline levels in B vitamins to predict the RSA occurrence as possible.


Assuntos
Aborto Habitual , Vitaminas , Feminino , Humanos , Adulto , Aborto Habitual/etiologia , Gravidez , Estudos Transversais , Modelos de Riscos Proporcionais , Espectrometria de Massas em Tandem/métodos , Solubilidade , Fatores de Risco , Água/química
6.
Chem Commun (Camb) ; 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308398

RESUMO

Transition metal-catalyzed cleavage and reconstruction of the C-P bond provides a highly efficient and rapid method for the transformation of organophosphine compounds. In this study, a novel and general protocol for the palladium-catalyzed C(sp3)-P(V) bond cleavage of free α-aminophosphonates and subsequent functionalization via C-P bond recombination has been developed. The reaction exhibits high reactivity between the C(sp3)-P bond and halides, accommodating a wide range of substrates and enabling the rapid synthesis of aryl, alkenyl, and alkyl organophosphine molecules. Additionally, the synthetic utility is validated by gram-scale synthesis, and the reaction process is corroborated by mechanistic experiments.

8.
Insects ; 15(9)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39336604

RESUMO

One new genus (Ocrognethoda gen. nov.) and three new species of webspinners (Ocrognethoda olivea gen. et sp. nov., Gnethoda lata sp. nov. and Parasorellembia hamata sp. nov.) are described from the Upper Cretaceous of Myanmar amber. Ocrognethoda olivea gen. et sp. nov. and Gnethoda lata sp. nov. are attributed to the family Clothodidae due to their simplified and symmetrical male terminalia, in which the tenth tergum is undivided. Parasorellembia hamata sp. nov. is classified in the family Scelembiidae by a specialized abdominal apex: fused cerci, a broad right hemitergite of the tenth abdominal tergite, and ocelli presence. Moreover, based on the discovery of new genus and species, the male terminalia of Clothodidae and Sorellembiinae are briefly discussed.

9.
World Neurosurg ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39332759

RESUMO

BACKGROUND: Osteoporosis and degenerative disc disease (DDD) are prevalent in the elderly population. Damage to the vertebral endplate, which impairs nutrient supply to the disc, serves as both a significant initiator and a hallmark of DDD. This study was aimed to explore the association between osteoporosis and endplate damage. METHODS: This retrospective study included 205 patients with DDD who were treated at tianjin hospital from January 2019 to May 2023. We collected data on age, sex, body mass index (BMI), phantom-less quantitative computed tomography (PL-QCT) values, and total endplate scores (TEPS). The average PL-QCT value of L1-L4 and TEPS were used to represent volumetric bone mineral density (v-BMD) and the degree of endplate damage, respectively. Based on the average PL-QCT value of L1 and L2, patients were divided into three groups: normal group (BMD > 120 mg/cm3), osteopenic group (80 mg/cm3 ≤ BMD ≤ 120 mg/cm3), and osteoporosis group (BMD < 80 mg/cm3). Multiple linear regression models were used to identify independent factors associated with endplate damage. RESULTS: The overall TEPS (4.3±1.3 vs 5.0±1.0 vs 5.9±1.5, p<0.01) and segment (L1/2-L4/5) TEPS (p<0.05) in each group showed significant difference (R=-0.5), increasing in order from normal group to osteoporosis group. A significant negative correlation was found between TEPS and PL-QCT values in overall and each segments (p<0.001). The PL-QCT values and age (p<0.05) were independent factors influencing endplate damage. There were significant differences in the average number of TEPS ≥7 segments per patient among the three groups, with 1.16, 0.41, and 0.2 segments/person from osteoporosis group to normal group. CONCLUSIONS: Our study showed a significant positive correlation between osteoporosis and endplate damage. Attention is warranted for patients with osteopenia to prevent progression to osteoporosis, potentially leading to exacerbated DDD. The management of patients with both DDD and osteoporosis necessitates comprehensive treatment strategies that address both the BMD and endplate aspects of these conditions.

10.
Int J Biol Macromol ; 280(Pt 3): 135931, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39322152

RESUMO

The wound microenvironment, often characterized by alkaline pH and severe hypoxia, presents significant challenges to the healing of bacterial-infected wounds. While considerable research has focused on improving wound healing through effective bacterial elimination using advanced therapeutic approaches, the importance of regulating the wound microenvironment has received less emphasis. In this work, we developed a biocompatible hydrogel, HTFC, by incorporating CaO2 nanoparticles (CaO2 NPs) into a gel formed by tannic acid (TA), hyaluronic acid (HA), and Fe3+. The HA and TA in HTFC hydrogel help to create a slightly acidic microenvironment, facilitating the decomposition of CaO2 NPs to release H2O2 for chemodynamic therapy (CDT). The reduction properties of TA promote the recycling of Fe3+/Fe2+, enhancing CDT efficacy and partially converting H2O2 to O2, thereby alleviating hypoxia. Additionally, FeIIITA complexes in HTFC enhance CDT through photothermal therapy (PTT)-induced improvement of the Fenton reaction. This multifunctional hydrogel, with its synergistic effects of PTT and CDT, along with its ability to remodel the wound microenvironment from hypoxic and alkaline to normoxic and acidic, accelerates the bacterial-infected wound healing process.

11.
Oncol Ther ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217582

RESUMO

The gut microbiota plays a crucial role in maintaining homeostasis in the human gastrointestinal tract. Numerous studies have shown a strong association between the gut microbiota and the emergence and progression of various diseases. Leukemia is one of the most common hematologic malignancies. Although standardized protocols and expert consensus have been developed for routine diagnosis and treatment, limitations remain due to individual differences. Nevertheless, a large number of studies have established a link between the gut microbiota and leukemia, with disturbances in the gut microbiota directly or indirectly affecting the development of leukemia. However, the causal relationship between the two remains unclear, and studying and exploring the causal relationship may open up entirely new avenues and protocols for use in the prevention and/or treatment of leukemia, offering new insights into diagnosis and treatment. In this review, the intricate relationship between the gut microbiota and leukemia is explored in depth, including causal associations, metabolite effects, therapeutic applications, and complications. Based on the characteristics of the gut microbiota, the future applications and prospects of gut microbiota are discussed to provide useful information for clinical treatment of leukemia.

12.
Adv Mater ; : e2408678, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221659

RESUMO

As an age-related disease, intervertebral disc degeneration is closely related to inflammation and aging. Inflammatory cytokines and cellular senescence collectively contribute to the degradation of intervertebral disc. Blocking this synergy reduces disc extracellular matrix damage caused by inflammation and aging. In this study, drug-loaded nanofibers with sequential targeting functions are constructed through intelligent response, hydrophilicity, and in situ self-assembly empowerment of flurbiprofen. The peptide precursor responds to the cleavage of overexpressed MMP-2 in the degenerative intervertebral disc microenvironment (intracellular and extracellular), resulting in the formation of self-assembled nanofibers that enable the on-demand release of flurbiprofen and COX-2 response. In vitro, Comp. 1 (Flurbiprofen-GFFYPLGLAGEEEERGD) reduces the expression of inflammation-related genes and proteins and the polarization of M1 macrophages by competitively inhibiting COX-2 and increases the expression of extracellular matrix proteins COL-2 and aggrecan. Additionally, it can reduce the expression of Senescence-Associated Secretory Phenotype and DNA damage in aged nucleus pulposus cells and promote the recovery of proliferation and cell cycle. In vivo, drug-loaded nanofibers delay intervertebral disc degeneration by inhibiting inflammation and preventing the accumulation of senescent cells. Therefore, the sequentially targeted self-assembled drug-loaded nanofibers can delay intervertebral disc degeneration by blocking the synergistic effect of inflammatory cytokines and cellular senescence.

13.
J Microbiol Biotechnol ; 34(11): 1-10, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39317683

RESUMO

Xiaoqu, a pivotal starter in baijiu fermentation, provides the most microflora and enzymes to initiate and maintain baijiu brewing. This study aims to explore the differences in microbiota and enzyme activities among Xiaoqu samples from seven provinces in southern China using high-throughput sequencing, plate isolation, and activity detection. The analyses revealed significant differences in bacterial and fungal communities across the samples. A total of 22 bacterial species and 17 target fungal species were isolated and identified. Predominant bacteria included Bacillus (Bacillus subtilis) and lactic acid bacteria (LABs), while the fungal communities were primarily composed of yeasts (Saccharomyces cerevisiae) and various molds. The activities of α-amylase and glucoamylase varied significantly among the samples, and samples from HN1 and GZ2 exhibited the highest activities. Correlation analyses highlighted the pivotal role of LABs in maintaining acidity and the importance of molds and yeasts in the saccharification and fermentation processes. These findings shed light on the microbial composition and diversity of Xiaoqu and the critical role of microbes in baijiu production. Moreover, they suggested potential microbial resources for developing artificial Xiaoqu via synthetic microbial community in the future, enhancing baijiu fermentation efficiency and overall product quality.

14.
Comput Struct Biotechnol J ; 23: 3020-3029, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39171252

RESUMO

Colorectal cancer (CRC) is the third most diagnosed cancer and the second deadliest cancer worldwide representing a major public health problem. In recent years, increasing evidence has shown that microRNA (miRNA) can control the expression of targeted human messenger RNA (mRNA) by reducing their abundance or translation, acting as oncogenes or tumor suppressors in various cancers, including CRC. Due to the significant up-regulation of oncogenic miRNAs in CRC, elucidating the underlying mechanism and identifying dysregulated miRNA targets may provide a basis for improving current therapeutic interventions. In this paper, we proposed Gra-CRC-miRTar, a pre-trained nucleotide-to-graph neural network framework, for identifying potential miRNA targets in CRC. Different from previous studies, we constructed two pre-trained models to encode RNA sequences and transformed them into de Bruijn graphs. We employed different graph neural networks to learn the latent representations. The embeddings generated from de Bruijn graphs were then fed into a Multilayer Perceptron (MLP) to perform the prediction tasks. Our extensive experiments show that Gra-CRC-miRTar achieves better performance than other deep learning algorithms and existing predictors. In addition, our analyses also successfully revealed 172 out of 201 functional interactions through experimentally validated miRNA-mRNA pairs in CRC. Collectively, our effort provides an accurate and efficient framework to identify potential miRNA targets in CRC, which can also be used to reveal miRNA target interactions in other malignancies, facilitating the development of novel therapeutics. The Gra-CRC-miRTar web server can be found at: http://gra-crc-mirtar.com/.

15.
Food Chem X ; 23: 101637, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39108628

RESUMO

The effects of dry-salted and salt-fermented processing on the physicochemical characteristics and microbial communities of Yacai were systematically investigated. The results showed that the contents of total acid, amino acid nitrogen (AAN) and nitrite in the final products of dry-salted Yacai were greater than those in salt-fermented Yacai. Lactic acid was the dominant organic acid in the two types of Yacai. Dry-salted processing is more conducive to forming a high-quality reddish-brown color. During whole pickling process, the microbial diversity of dry-salted Yacai was higher than that of salt-fermented Yacai, particularly in the early and middle stages of fermentation. For dry-salted Yacai, 8 bacteria (Natribacillus, Chromohalobacter, Marinococcus, Lentibacillus, Nesterenkonia, Gracilibacillus, Oceanobacillus and Tetragenococcus) and 1 fungus (Zygosaccharomyces) showed a significant positive correlation with AAN. For salt-fermented Yacai, 8 bacteria (Gracilibacillus, Alkalibacillus, Oceanobacillus, Virgibacillus, Lentibacillus, Salibacterium, Chromohalobacter and Tetragenococcus) and 3 fungi (Zygosaccharomyces, Millerozyma, and Wickerhamomyces) exhibited significant positive correlations with AAN.

16.
Sci Total Environ ; 951: 175430, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39128524

RESUMO

Biomass burning is a primary source of atmospheric nitrogen oxide (NOx), however, the lack of isotopic fingerprints from biomass burning limits their use in tracing atmospheric nitrate (NO3-) and NOx. A total of 25 biomass fuels from 10 provinces and regions in China were collected, and the δ15N values of biomass fuels (δ15N-biomass) and δ15N-NOx values of biomass burning (δ15N-NOx values of BB, open burning, and rural cooking stove burning) were determined. The δ15N-NOx values of open burning and rural cooking stove burning ranged from -0.8 ‰ to 11.6 ‰ and 0.8 ‰ to 9.5 ‰, respectively, indicating a significant linear relation with δ15N-biomass. Based on the measured δ15N-NOx values of BB and biomass burning emission inventory data, the δ15N-NOx values of BB in different provinces and regions of China were calculated using the δ15N-NOx model, with a mean value of 5.0 ± 1.8 ‰. The spatial variations in the estimated δ15N-NOx values of BB in China were mainly controlled by the differences in the δ15N-NOx values and the proportions of NOx emissions from various straw burning activities in provinces and regions of China. Furthermore, by using the combined local emissions of biomass burning with regional transportations of NOx based on air-mass backward trajectories, we established an improved δ15N-NOx model and obtained more accurate δ15N-NOx values of BB in regions (2.3 ‰ to 8.4 ‰). By utilising the reported δ15N-NOx values of precipitation and particulate matter from 21 cities in China and the more accurate δ15N-NOx values of BB, the NOx contributions from four sources (mobile sources, coal combustion, biomass burning, and microbial N cycle) at the national scale were estimated using a Bayesian model. The significant contributions of biomass burning (20.9 % to 44.3 %) to NOx emissions were revealed, which is vital for controlling NOx emissions in China.

17.
Eur Spine J ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103616

RESUMO

BACKGROUND: Osteoporotic vertebral compression fracture (OVCF) is a common consequence of osteoporosis and can significantly impact the quality of life for affected individuals. Despite treatment options such as vertebroplasty and kyphoplasty, many patients continue to experience residual back pain (RBP) even after the fracture has healed. The incidence of RBP after OVCF treatment varies among studies, and there is a need for further research to understand the risk factors associated with RBP. METHODS: A systematic review and meta-analysis were conducted following the PRISMA guidelines. Electronic databases were searched, and relevant studies were selected based on inclusion and exclusion criteria. Data extraction and quality assessment were performed independently by two authors. Statistical analysis included single-proportion meta-analyses and pooling of odds ratios (OR) using the inverse-variance method, to calculate the overall incidences of RBP and cement leakage and identify risk factors associated with RBP. RESULTS: A total of 19 studies were included in the analysis. The overall incidences of RBP and cement leakage were found to be 16% and 18%, respectively. Several risk factors were identified, including gender, bone mineral density, depression, baseline visual analog scale (VAS) score, intravertebral vacuum cleft, number of fractured segments, cement distribution, history of vertebral fracture, thoracolumbar fascial injury, and fracture non-union. CONCLUSIONS: This study provides potential value within the scope of the incidence and risk factors of RBP following treatment of OVCFs. The identified risk factors can help clinicians identify high-risk patients and tailor appropriate interventions. Future research should focus on standardizing the definition of RBP and patient selection criteria to improve the accuracy of estimates and facilitate better management strategies for OVCF patients.

18.
Front Microbiol ; 15: 1412503, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109205

RESUMO

"Green-covering and red-heart" Guanyin Tuqu (GRTQ), as a type of special fermentation starter, is characterized by the "green-covering" formed on the surface of Guanyin Tuqu (SQ) and the "red-heart" in the center of Guanyin Tuqu (CQ). However, the mechanisms that promote temporal succession in the GRTQ microbial ecology and the formation of "green-covering and red-heart" characteristics remain unclear. Herein, we correlated the temporal profiles of microbial community succession with the main environmental variables (temperature, moisture, and acidity) and spatial position (center and surface) in GRTQ throughout fermentation. According to the results of high-throughput sequencing and culture-dependent methods, the microbial communities in the CQ and SQ demonstrated functional complementarity. For instance, the bacterial richness index of the CQ was greater than that of SQ, and the fungal richness index of the SQ was greater than that of CQ at the later stage of fermentation. Furthermore, Saccharomycopsis, Saccharomyces, Aspergillus, Monascus, Lactobacillus, Bacillus, Rhodanobacter, and Chitinophaga were identified as the dominant microorganisms in the center, while the surface was represented by Saccharomycopsis, Aspergillus, Monascus, Lactobacillus, Acetobacter, and Weissella. By revealing the physiological characteristics of core microorganisms at different spatial positions of GRTQ, such as Aspergillus clavatus and Monascus purpureus, as well as their interactions with environmental factors, we elucidated the color formation mechanism behind the phenomenon of "green" outside and "red" inside. This study provides fundamental information support for optimizing the production process of GRTQ.

19.
J Colloid Interface Sci ; 677(Pt A): 599-609, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39111094

RESUMO

Harnessing the inexhaustible solar energy for water splitting is regarded one of the most promising strategies for hydrogen production. However, sluggish kinetics of oxygen evolution reaction (OER) and expensive photovoltaics have hindered commercial viability. Here, an adhesive-free electrodeposition process is developed for in-situ preparation of earth-abundant electrocatalysts on super-flat indium tin oxide (ITO) substrate. NiFe hydroxide exhibited prominent OER performance, achieving an ultra-low overpotential of 236 mV at 10 mA/cm2 in alkaline solution. With the superior OER activity, we achieved an unassisted solar water splitting by series connected perovskite solar cells (PSCs) of 2 cm2 aperture area with NiFe/ITO//Pt electrodes, yielding overall solar to hydrogen (STH) efficiency of 13.75 %. Furthermore, we upscaled the monolithic facility to utilize perovskite solar module for large-scale hydrogen production and maintained an approximate operating current of 20 mA. This creative strategy contributes to the decrease of industrial manufacturing expenses for perovskite-based photovoltaic-electrochemical (PV-EC) hydrogen production, further accelerating the conversion and utilization of carbon-free energy.

20.
Small ; : e2405982, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115088

RESUMO

Sodium-ion batteries are increasingly recognized as ideal for large-scale energy storage applications. Alluaudite Na2+2 δFe2- δ(SO4)3 has become one of the focused cathode materials in this field. However, previous studies employing aqueous-solution synthesis often overlooked the formation mechanism of the impurity phase. In this study, the nonequilibrium evolution mechanism between Na2+2 δFe2- δ(SO4)3 and impurities by adjusting ratios of the Na2SO4/FeSO4·7H2O in the binary system is investigated. Then an optimal ratio of 0.765 with reduced impurity content is confirmed. Compared to the poor electrochemical performance of the Na2.6Fe1.7(SO4)3 (0.765) cathode, the optimized Na2.6Fe1.7(SO4)3@CNTs (0.765@CNTs) cathode, with improved electronic and ionic conductivity, demonstrates an impressive discharge specific capacity of 93.8 mAh g-1 at 0.1 C and a high-rate capacity of 67.84 mAh g-1 at 20 C, maintaining capacity retention of 71.1% after 3000 cycles at 10 C. The Na2.6Fe1.7(SO4)3@CNTs//HC full cell reaches an unprecedented working potential of 3.71 V at 0.1 C, and a remarkable mass-energy density exceeding 320 Wh kg-1. This work not only provides comprehensive guidance for synthesizing high-voltage Na2+2 δFe2- δ(SO4)3 cathode materials with controllable impurity content but also lays the groundwork of sodium-ion batteries for large-scale energy storage applications.

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