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1.
Small ; 20(26): e2310426, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229551

RESUMO

Sodium-ion batteries (SIBs), as the next-generation high-performance electrochemical energy storage devices, have attracted widespread attention due to their cost-effectiveness and wide geographical distribution of sodium. As a crucial component of the structure of SIBs, the anode material plays a crucial role in determining its electrochemical performance. Significantly, metal phosphide exhibits remarkable application prospects as an anode material for SIBs because of its low redox potential and high theoretical capacity. However, due to volume expansion limitations and other factors, the rate and cycling performance of metal phosphides have gradually declined. To address these challenges, various viable solutions have been explored. In this paper, the recent research progress of metal phosphide materials for SIBs is systematically reviewed, including the synthesis strategy of metal phosphide, the storage mechanism of sodium ions, and the application of metal phosphide in electrochemical aspects. In addition, future challenges and opportunities based on current developments are presented.

2.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003311

RESUMO

Brassinosteroids (BRs), the sixth major phytohormone, can regulate plant salt tolerance. Many studies have been conducted to investigate the effects of BRs on plant salt tolerance, generating a large amount of research data. However, a meta-analysis on regulating plant salt tolerance by BRs has not been reported. Therefore, this study conducted a meta-analysis of 132 studies to elucidate the most critical physiological mechanisms by which BRs regulate salt tolerance in plants from a higher dimension and analyze the best ways to apply BRs. The results showed that exogenous BRs significantly increased germination, plant height, root length, and biomass (total dry weight was the largest) of plants under salt stress. There was no significant difference between seed soaking and foliar spraying. However, the medium method (germination stage) and stem application (seedling stage) may be more effective in improving plant salt tolerance. BRs only inhibit germination in Solanaceae. BRs (2 µM), seed soaking for 12 h, and simultaneous treatment with salt stress had the highest germination rate. At the seedling stage, the activity of Brassinolide (C28H48O6) was higher than that of Homobrassinolide (C29H50O6), and post-treatment, BRs (0.02 µM) was the best solution. BRs are unsuitable for use in the germination stage when Sodium chloride is below 100 mM, and the effect is also weakest in the seedling stage. Exogenous BRs promoted photosynthesis, and antioxidant enzyme activity increased the accumulation of osmoregulatory and antioxidant substances and reduced the content of harmful substances and Na+, thus reducing cell damage and improving plant salt tolerance. BRs induced the most soluble protein, chlorophyll a, stomatal conductance, net photosynthetic rate, Glutathione peroxidase, and root-Ca2+, with BRs causing Ca2+ signals in roots probably constituting the most important reason for improving salt tolerance. BRs first promoted the accumulation of Ca2+ in roots, which increased the content of the above vital substances and enzyme activities through the Ca2+ signaling pathway, improving plant salt tolerance.


Assuntos
Antioxidantes , Brassinosteroides , Brassinosteroides/farmacologia , Brassinosteroides/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Tolerância ao Sal , Clorofila A/metabolismo , Plântula/metabolismo , Raízes de Plantas
3.
Dalton Trans ; 53(21): 9081-9091, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38738658

RESUMO

Lithium-ion batteries (LIBs) are greatly limited in their practical application because of their poor cycle performance, low conductivity and volume expansion. Herein, molten salts (MSs) FeCl3·6H2O-NMP with low temperature via simple preparation are used as the anode material of LIBs for the first time to break through the bottleneck of LIBs. The good fluidity and high self-healing of FeCl3·6H2O-NMP effectively avoid the collapse and breakage of the structure. Based on this feature, the initial discharge specific capacity reached 770.28 mA h g-1, which was more than twice that of the commercial graphite anode. After 200 cycles at a current density of 100 mA g-1, the specific capacity did not decrease rather it was found to be higher than the initial discharge specific capacity, reaching 867.24 mA h g-1. Besides, the good conductivity of MSs provides convenience for the removal and intercalation of Li+. The active H sites that can combine with lithium ions form LiH and provide capacity for LIBs. Density functional theory (DFT) calculation also provided theoretical proof for the mechanism of LIBs.

4.
JMIR Mhealth Uhealth ; 12: e48777, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924786

RESUMO

BACKGROUND: Early detection of cognitive impairment or dementia is essential to reduce the incidence of severe neurodegenerative diseases. However, currently available diagnostic tools for detecting mild cognitive impairment (MCI) or dementia are time-consuming, expensive, or not widely accessible. Hence, exploring more effective methods to assist clinicians in detecting MCI is necessary. OBJECTIVE: In this study, we aimed to explore the feasibility and efficiency of assessing MCI through movement kinetics under tablet-based "drawing and dragging" tasks. METHODS: We iteratively designed "drawing and dragging" tasks by conducting symposiums, programming, and interviews with stakeholders (neurologists, nurses, engineers, patients with MCI, healthy older adults, and caregivers). Subsequently, stroke patterns and movement kinetics were evaluated in healthy control and MCI groups by comparing 5 categories of features related to hand motor function (ie, time, stroke, frequency, score, and sequence). Finally, user experience with the overall cognitive screening system was investigated using structured questionnaires and unstructured interviews, and their suggestions were recorded. RESULTS: The "drawing and dragging" tasks can detect MCI effectively, with an average accuracy of 85% (SD 2%). Using statistical comparison of movement kinetics, we discovered that the time- and score-based features are the most effective among all the features. Specifically, compared with the healthy control group, the MCI group showed a significant increase in the time they took for the hand to switch from one stroke to the next, with longer drawing times, slow dragging, and lower scores. In addition, patients with MCI had poorer decision-making strategies and visual perception of drawing sequence features, as evidenced by adding auxiliary information and losing more local details in the drawing. Feedback from user experience indicates that our system is user-friendly and facilitates screening for deficits in self-perception. CONCLUSIONS: The tablet-based MCI detection system quantitatively assesses hand motor function in older adults and further elucidates the cognitive and behavioral decline phenomenon in patients with MCI. This innovative approach serves to identify and measure digital biomarkers associated with MCI or Alzheimer dementia, enabling the monitoring of changes in patients' executive function and visual perceptual abilities as the disease advances.


Assuntos
Disfunção Cognitiva , Humanos , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Testes Neuropsicológicos/normas , Mãos/fisiopatologia , Idoso de 80 Anos ou mais , Inquéritos e Questionários , Pesquisa Qualitativa
5.
Dalton Trans ; 53(11): 4900-4921, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38321942

RESUMO

With the advent of lithium-ion batteries (LIBs), the selection and application of electrode materials have been the subject of much discussion and study. Among them, graphite has been widely investigated for use as electrode materials in LIBs due to its abundant resources, low cost, safety and electrochemical diversity. While it is commonly recognized that conventional graphite materials utilized for commercial purposes have a limited theoretical capacity, there has been a steady emergence of new and improved carbonaceous materials for use as anodes in light of the progressive development of LIBs. In this paper, the latest research progress of various carbon materials in LIBs is systematically and comprehensively reviewed. Firstly, the rocking chair charging and discharging mechanism of LIBs is briefly introduced in this paper, using graphite anodes as an example. After that, the general categories of carbonaceous materials are highlighted, and the recent research on the recent progress of various carbonaceous materials (graphite-based, amorphous carbon-based, and nanocarbon-based) used in LIB anodes is presented separately based on the classification of the structural morphology, emphasizing the influence of the morphology and structure of carbon-based materials on the electrochemical performance of the batteries. Finally, the current challenges of carbonaceous materials in LIB applications and the future development of other novel carbonaceous materials are envisioned.

6.
J Agric Food Chem ; 71(50): 19949-19957, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38018896

RESUMO

Exopolysaccharides (EPS) are macromolecular substances with environmentally beneficial properties. At present, some reports have focused on the effects of EPS on plants salt stress; however, few studies have carried out a deeper characterization of the EPS components involved in Na+ binding. We investigated the mechanism of Na+ adsorption by Pseudomonas simiae MHR6 EPS and the regulation of ion homeostasis in maize under salt stress. The results showed that NaCl at 6% significantly inhibited MHR6 growth but enhanced EPS secretion. The chemical composition of the EPS varied in response to an increased NaCl concentration, and the proportion of polysaccharides was consistently higher than that of proteins. The highest Na+ adsorption was observed for 6% NaCl. The FTIR, SEM, and EDX results further indicated that EPS effectively biosorbed Na+. Furthermore, adding EPS improved Na+/K+ homeostasis in maize under salt stress. These results suggest that MHR6 EPS has potential for future development and utilization as a plant growth biostimulant in saline-alkali land.


Assuntos
Estresse Fisiológico , Zea mays , Zea mays/metabolismo , Adsorção , Cloreto de Sódio/farmacologia , Estresse Salino , Íons , Sódio/metabolismo , Homeostase , Potássio/metabolismo
7.
Dalton Trans ; 52(9): 2548-2560, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36752364

RESUMO

Room-temperature sodium-sulfur batteries (RT-Na/S batteries) with high reversible capacity (1675 mA h g-1) and excellent energy density (1274 W h kg-1) based on abundant resources of the metal Na have become a research hotspot recently. However, the intermediate product sodium polysulfides (NaPSs) generated during the charge-discharge process are easily dissolved in the ether electrolyte and transferred from the sulfur cathode to the metallic sodium surface, resulting in rapid capacity decay (shuttle effect), which seriously affects the practical application of RT-Na/S batteries. Herein, the mechanism and recent research progress in suppressing the shuttle effect of the sulfur cathode in RT-Na/S batteries are summarized. Strategies such as carbon-based materials physically fixing NaPSs, polar materials absorbing NaPSs to reduce their dissolution, and catalytic materials accelerating the transformation of NaPSs into final products are provided. Challenges and insights into high-performance sulfur electrodes for optimizing RT-Na/S batteries are discussed.

8.
Brain Sci ; 13(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37626578

RESUMO

Significant advances in sensor technology and virtual reality (VR) offer new possibilities for early and effective detection of mild cognitive impairment (MCI), and this wealth of data can improve the early detection and monitoring of patients. In this study, we proposed a non-invasive and effective MCI detection protocol based on electroencephalogram (EEG), speech, and digitized cognitive parameters. The EEG data, speech data, and digitized cognitive parameters of 86 participants (44 MCI patients and 42 healthy individuals) were monitored using a wearable EEG device and a VR device during the resting state and task (the VR-based language task we designed). Regarding the features selected under different modality combinations for all language tasks, we performed leave-one-out cross-validation for them using four different classifiers. We then compared the classification performance under multimodal data fusion using features from a single language task, features from all tasks, and using a weighted voting strategy, respectively. The experimental results showed that the collaborative screening of multimodal data yielded the highest classification performance compared to single-modal features. Among them, the SVM classifier using the RBF kernel obtained the best classification results with an accuracy of 87%. The overall classification performance was further improved using a weighted voting strategy with an accuracy of 89.8%, indicating that our proposed method can tap into the cognitive changes of MCI patients. The MCI detection scheme based on EEG, speech, and digital cognitive parameters proposed in this study provides a new direction and support for effective MCI detection, and suggests that VR and wearable devices will be a promising direction for easy-to-perform and effective MCI detection, offering new possibilities for the exploration of VR technology in the field of language cognition.

9.
Comput Biol Med ; 152: 106418, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566627

RESUMO

Subtle changes in fine motor control and quantitative electroencephalography (qEEG) in patients with mild cognitive impairment (MCI) are important in screening for early dementia in primary care populations. In this study, an automated, non-invasive and rapid detection protocol for mild cognitive impairment based on handwriting kinetics and quantitative EEG analysis was proposed, and a classification model based on a dual fusion of feature and decision layers was designed for clinical decision-marking. Seventy-nine volunteers (39 healthy elderly controls and 40 patients with mild cognitive impairment) were recruited for this study, and the handwritten data and the EEG signals were performed using a tablet and MUSE under four designed handwriting tasks. Sixty-eight features were extracted from the EEG and handwriting parameters of each test. Features selected from both models were fused using a late feature fusion strategy with a weighted voting strategy for decision making, and classification accuracy was compared using three different classifiers under handwritten features, EEG features and fused features respectively. The results show that the dual fusion model can further improve the classification accuracy, with the highest classification accuracy for the combined features and the best classification result of 96.3% using SVM with RBF kernel as the base classifier. In addition, this not only supports the greater significance of multimodal data for differentiating MCI, but also tests the feasibility of using the portable EEG headband as a measure of EEG in patients with cognitive impairment.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Disfunção Cognitiva/diagnóstico , Eletroencefalografia/métodos , Escrita Manual , Doença de Alzheimer/diagnóstico
10.
Dalton Trans ; 51(25): 9584-9590, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35697342

RESUMO

Lithium-ion batteries with a stable circulation capacity, high energy density and good safety are widely used in automobiles, mobile phones, manufacturing and other fields. MOs due to their large theoretical capacity, simple processing and abundant reserves, and used as anode materials for LIBs, have attracted much attention. Three electrochemical mechanisms of MOs are reviewed in this paper. In addition, research progress of MOs and prospects for their further applications in LIBs are summarized.

11.
Dalton Trans ; 51(16): 6390-6398, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35388395

RESUMO

With a high specific capacity, MoP2 has been identified as an ideal electrode material for LIBs. However, the specific capacity is negatively affected due to its poor conductivity and severe volume expansion during insertion and extraction of Li+. In this paper, MoP2-C synthesized by using a Mo-MOF as a precursor, with the generation of C, can effectively solve the agglomeration problem in the synthesis process and alleviate serious volume changes during cycling. Due to the lack of carbon sources provided by a Mo-MOF, the conductivity of MoP2-C cannot be greatly improved. Therefore, rGO and PPy are added to improve the conductivity of MoP2 and further increase the stability of the structure. Compared with MoP2/C and MoP2/C@PPy, MoP2/C@rGO exhibits the highest initial discharge specific capacity of 1208 mA h g-1 at a current density of 100 mA g-1 and rate performances of 830, 750, 630, 550, and 430 mA h g-1 with the current density increasing from 100 mA g-1 to 2000 mA g-1. Notably, the specific capacity remains at 640 mA h g-1 at a current density of 100 mA g-1 after 100 cycles. Followed by 200 cycles at a current density of 2000 mA h g-1, the specific capacity remains at 395 mA h g-1 with a capacity retention rate of 80%.

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