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1.
Angew Chem Int Ed Engl ; 63(24): e202403661, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38613727

RESUMO

The development of highly producible and interfacial compatible in situ polymerized electrolytes for solid-state lithium metal batteries (SSLMBs) have been plagued by insufficient transport kinetics and uncontrollable dendrite propagation. Herein, we seek to explore a rationally designed nanofiber architecture to balance all the criteria of SSLMBs, in which La0.6Sr0.4CoO3-δ (LSC) enriched with high valence-state Co species and oxygen vacancies is developed as electronically conductive nanofillers embedded within ZnO/Zn3N2-functionalized polyimide (Zn-PI) nanofiber framework for the first time, to establish Li+ transport highways for poly vinylene carbonate (PVC) electrolyte and eliminate nonuniform Li deposits. Revealed by characterization and theoretical calculation under electric field, the positive-negative electrical dipole layer in LSC derived from electron migration between Co and O atoms aids in accelerating Li+ diffusion kinetics through densified electric field around filler particle, featuring a remarkable ionic conductivity of 1.50 mS cm-1 at 25 °C and a high Li+ transference number of 0.91 without the risk of electron leakage. Integrating with the preferential sacrifice of ZnO/Zn3N2 on PI nanofiber upon immediate detection of dendritic Li, which takes part in reconfiguring hierarchical SEI chemistry dominated by LixNy/Li-Zn alloy inner layer and LiF outer layer, SSLMBs are further endowed with prolonged cycling lifespan and exceptional rate capability.

2.
Small ; : e2307942, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054774

RESUMO

Employing nanofiber framework for in situ polymerized solid-state lithium metal batteries (SSLMBs) is impeded by the insufficient Li+ transport properties and severe dendritic Li growth. Both critical issues originate from the shortage of Li+ conduction highways and nonuniform Li+ flux, as randomly-scattered nanofiber backbone is highly prone to slippage during battery assembly. Herein, a robust fabric of Li0.33 La0.56 Ce0.06 Ti0.94 O3-δ /polyacrylonitrile framework (p-LLCTO/PAN) with inbuilt Li+ transport channels and high interfacial Li+ flux is reported to manipulate the critical current density of SSLMBs. Upon the merits of defective LLCTO fillers, TFSI- confinement and linear alignment of Li+ conduction pathways are realized inside 1D p-LLCTO/PAN tunnels, enabling remarkable ionic conductivity of 1.21 mS cm-1 (26 °C) and tLi+ of 0.93 for in situ polymerized polyvinylene carbonate (PVC) electrolyte. Specifically, molecular reinforcement protocol on PAN framework further rearranges the Li+ highway distribution on Li metal and alters Li dendrite nucleation pattern, boosting a homogeneous Li deposition behavior with favorable SEI interface chemistry. Accordingly, excellent capacity retention of 76.7% over 1000 cycles at 2 C for Li||LiFePO4 battery and 76.2% over 500 cycles at 1 C for Li||LiNi0.5 Co0.2 Mn0.3 O2 battery are delivered by p-LLCTO/PAN/PVC electrolyte, presenting feasible route in overcoming the bottleneck of dendrite penetration in in situ polymerized SSLMBs.

3.
ACS Appl Mater Interfaces ; 11(11): 10642-10650, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30794370

RESUMO

Lowering the operating temperature is a universal R&D challenge for the development of low-temperature (<600 °C) solid oxide fuel cells (SOFCs) that meet the demands of commercialization. Regarding the traditional electrolyte materials of SOFCs, bulk diffusion is the main ionic conduction mechanism, which is primarily affected by the bulk density and operating temperatures. In this study, we report a new mechanism for the Ce0.9Gd0.1O2-δ (GDC) electrolyte based on a nanocrystalline structure with surface or grain boundary conduction, exhibiting an extremely high ionic conductivity of 0.37 S·cm-1 at 550 °C. The fuel cell with the nanocrystalline structure GDC electrolyte (0.5 mm in thickness) can deliver a remarkable peak power density of 591.8 mW·cm-2 at 550 °C, which is approximately 3.5 times higher than that for the cell with the GDC electrolyte densified at 1550 °C. An amorphous layer enriched by oxygen vacancies was found at the surface of the nano-GDC particles in the fuel cell test atmosphere, which was attributed to the ion conduction channel of the grain boundary diffusion. The ionic conduction at the interfaces between the particles was discovered to be the dominant conduction mechanism of the nanocrystalline structure GDC electrolyte. Oxygen ions and protons were determined to be the charge carriers in this interfacial conduction phenomenon, and the conduction of oxygen ions was dominant.

4.
Comput Intell Neurosci ; 2017: 5739301, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29403528

RESUMO

Eye movement can be regarded as a pivotal real-time input medium for human-computer communication, which is especially important for people with physical disability. In order to improve the reliability, mobility, and usability of eye tracking technique in user-computer dialogue, a novel eye control system with integrating both mouse and keyboard functions is proposed in this paper. The proposed system focuses on providing a simple and convenient interactive mode by only using user's eye. The usage flow of the proposed system is designed to perfectly follow human natural habits. Additionally, a magnifier module is proposed to allow the accurate operation. In the experiment, two interactive tasks with different difficulty (searching article and browsing multimedia web) were done to compare the proposed eye control tool with an existing system. The Technology Acceptance Model (TAM) measures are used to evaluate the perceived effectiveness of our system. It is demonstrated that the proposed system is very effective with regard to usability and interface design.


Assuntos
Atenção/fisiologia , Medições dos Movimentos Oculares/instrumentação , Movimentos Oculares , Interface Usuário-Computador , Adolescente , Adulto , Interfaces Cérebro-Computador , Simulação por Computador , Feminino , Humanos , Masculino , Software , Inquéritos e Questionários , Carga de Trabalho , Adulto Jovem
5.
Artigo em Zh | MEDLINE | ID: mdl-20135974

RESUMO

OBJECTIVE: To study the hook of hamate bone by anatomy and iconography methods in order to provide information for the clinical treatment of injuries to the hook of hamate bone and the deep branch of ulnar nerve. METHODS: Fifty-two upper limb specimens of adult corpses contributed voluntarily were collected, including 40 antisepticized old specimens and 12 fresh ones. The hook of hamate bone and its adjacent structure were observed. Twenty-four upper limbs selected randomly from specimens of corpses and 24 upper limbs from 12 healthy adults were investigated by computed tomography (CT) three-dimensional reconstruction, and then related data were measured. The measurement results of 24 specimens were analyzed statistically. RESULTS: The hook of hamate bone is an important component of ulnar carpal canal and carpal canal, and the deep branch of ulnar nerve is located closely in the inner front of the hook of hamate bone. The flexor tendons of the forth and the little fingers are in the innermost side, closely lie next to the outside of the hook of hamate bone. The hamate bone located between the capitate bone and the three-cornered bone with wedge-shaped. The medial-, lateral-, and front-sides are all facies articularis. The hook of hamate bone has an approximate shape of a flat plate. The position migrated from the body of the hamate bone, the middle of the hook and the enlargement of the top of the hook were given the names of "the basis of the hook", "the waist of the hook", and "the coronal of the hook", respectively. The short path of the basement are all longer than the short path of the waist. The long path of the top of the hook is the maximum length diameter of the hook of hamate bone, and is longer than the long path of the basement and the long path of the waist. The iconography shape and trait of the hook of hamate bone is similar to the anatomy result. There were no statistically significant differences (P > 0.05) between two methods in the seven parameters as follows: the long path of the basement of the hook, the short path of the basement of the hook, the long path of the waist of the hook, the short path of the waist of the hook, the long path of the top of the hook, the height of the hook, of hamate bone, and the distance between the top and the waist of the hook. CONCLUSION: The hook of hamate bone can be divided into three parts: the coronal part, the waist part, and the basal part; fracture of the hamate bone can be divided into fracture of the body, fracture of the hook, and fracture of the body and the hook. Fracture of the hook of hamate bone or fracture union can easily result in injure of the deep branch of ulnar nerve and the flexor tendons of the forth and the little fingers. The measurement results of CT three-dimensional reconstruction can be used as reference value directly in clinical treatments.


Assuntos
Hamato/anatomia & histologia , Articulação do Punho/anatomia & histologia , Adulto , Hamato/diagnóstico por imagem , Hamato/lesões , Humanos , Imageamento Tridimensional , Tomografia Computadorizada Espiral , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia
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