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1.
RSC Adv ; 14(12): 8195-8203, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38469199

ABSTRACT

Anodized TiO2 nanotube arrays (TNTAs) prepared by anodization have garnered widespread attention due to their unique structure and properties. In this study, we prepared TNTAs of varying lengths by controlling the anodization time. Among them, the nanotubes anodized for 2 h have an inner diameter of approximately 92 nm and a wall thickness of approximately 12 nm. Then we subjected amorphous TNTAs prepared by the anodization method to annealing treatments, systematically analyzing the evolution of morphology and structure with varying annealing temperatures. As the annealing temperature increases, the amorphous successively undergoes transitions to the anatase phase and then to the rutile phase. During the transition to the anatase phase, the structure of the nanotube array remains intact, with the complete preservation of the tubular array structure. However, during the transition to the rutile phase, the tubular array structure is destroyed. To address why the tubular array remains undamaged during the amorphous-to-anatase transition, we subjected amorphous TNTAs to annealing at 300 °C for different durations. Raman spectroscopy was employed for fit analysis, providing insights into the evolution of the molecular structure during the anatase phase transition. Finally, TNTAs annealed at different temperatures were incorporated into lithium-ion batteries. By combining XRD for semi-quantitative phase content and anatase particle size calculations, we established a correlation between structure and electrochemical performance. The results indicate a significant improvement in electrochemical performance for an amorphous-anatase structure obtained through annealing at 300 °C, providing insights for the design of high-performance energy storage materials.

2.
Materials (Basel) ; 16(21)2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37959554

ABSTRACT

Niobium pentoxide (Nb2O5), as an important dielectric and semiconductor material, has numerous crystal polymorphs, higher chemical stability than water and oxygen, and a higher melt point than most metal oxides. Nb2O5 materials have been extensively studied in electrochemistry, lithium batteries, catalysts, ionic liquid gating, and microelectronics. Nb2O5 polymorphs provide a model system for studying structure-property relationships. For example, the T-Nb2O5 polymorph has two-dimensional layers with very low steric hindrance, allowing for rapid Li-ion migration. With the ever-increasing energy crisis, the excellent electrical properties of Nb2O5 polymorphs have made them a research hotspot for potential applications in lithium-ion batteries (LIBs) and supercapacitors (SCs). The basic properties, crystal structures, synthesis methods, and applications of Nb2O5 polymorphs are reviewed in this article. Future research directions related to this material are also briefly discussed.

3.
Innovation (Camb) ; 4(4): 100458, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37416514
4.
J Chem Phys ; 158(11): 114703, 2023 Mar 21.
Article in English | MEDLINE | ID: mdl-36948826

ABSTRACT

Recently, Ni-rich LiNixCoyMn1-x-yO2 (x ≥ 0.8) draw significant research attention as cathode materials in lithium-ion batteries due to their superiority in energy density. However, the oxygen release and the transition metals (TMs) dissolution during the (dis)charging process lead to serious safety issues and capacity loss, which highly prevent its application. In this work, we systematically explored the stability of lattice oxygen and TM sites in LiNi0.8Co0.1Mn0.1O2(NCM811) cathode via investigating various vacancy formations during lithiation/delithiation, and properties such as the number of unpaired spins (NUS), net charges, and d band center were comprehensively studied. In the process of delithiation (x = 1 → 0.75 → 0), the vacancy formation energy of lattice oxygen [Evac(O)] has been identified to follow the order of Evac(O-Mn) > Evac(O-Co) > Evac(O-Ni), and Evac(TMs) shows a consistent trend with the sequence of Evac(Mn) > Evac(Co) > Evac(Ni), demonstrating the importance of Mn to stabilize the structural skeleton. Furthermore, the |NUS| and net charge are proved to be good descriptors for measuring Evac(O/TMs), which show linear correlations with Evac(O) and Evac(TMs), respectively. Li vacancy plays a pivotal role on Evac(O/TMs). Evac(O/TMs) at x = 0.75 vary extremely between the NiCoMnO layer (NCM layer) and the NiO layer (Ni layer), which correlates well with |NUS| and net charge in the NCM layer but aggregates in a small region in the Ni layer due to the effect of Li vacancies. In general, this work provides an in-depth understanding of the instability of lattice oxygen and transition metal sites on the (104) surface of Ni-rich NCM811, which might give new insights into oxygen release and transition metal dissolution in this system.

5.
Front Immunol ; 13: 975926, 2022.
Article in English | MEDLINE | ID: mdl-36189243

ABSTRACT

Immune dysfunction has been proposed as a factor that may contribute to disease progression. Emerging evidence suggests that immunotherapy aims to abolish cancer progression by modulating the balance of the tumor microenvironment. 4-1BB (also known as CD137 and TNFRS9), a member of tumor necrosis factor receptor superfamily, has been validated as an extremely attractive and promising target for immunotherapy due to the upregulated expression in the tumor environment and its involvement in tumor progression. More importantly, 4-1BB-based immunotherapy approaches have manifested powerful antitumor effects in clinical trials targeting 4-1BB alone or in combination with other immune checkpoints. In this review, we will summarize the structure and expression of 4-1BB and its ligand, discuss the role of 4-1BB in the microenvironment and tumor progression, and update the development of drugs targeting 4-1BB. The purpose of the review is to furnish a comprehensive overview of the potential of 4-1BB as an immunotherapeutic target and to discuss recent advances and prospects for 4-1BB in cancer therapy.


Subject(s)
Immunotherapy , Neoplasms , Tumor Necrosis Factor Receptor Superfamily, Member 9/immunology , Humans , Ligands , Receptors, Tumor Necrosis Factor , Tumor Microenvironment
6.
J Biochem Mol Toxicol ; 36(8): e23116, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35670019

ABSTRACT

Cytokines-mediated immunity is essential for the pathological development of rheumatoid arthritis (RA). Inhibition of signaling has suggested a potential remedial approach to RA. G protein-coupled receptor 4 (GPR4) has been proven to possess a broad range of physiological functions, but its function in synovial mast cells and RA is less reported. In this study, the protective effects of NE 52-QQ57, a GPR4 antagonist, against interleukin (IL)-33-challenged inflammatory response in activated synovial mast cells were investigated. We report that IL-33 amplified GPR4 expression in HMC-1 mast cells. The GPR4 antagonist NE 52-QQ57 alleviated IL-33-caused secretions of IL-17, interferon-γ, and tumor necrosis factor-α in HMC-1 mast cells. Furthermore, we note that NE 52-QQ57 reduced IL-33-induced expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9. Also, NE 52-QQ57 inhibited cyclooxygenase 2 and prostaglandin E2 expression in IL-33-challenged cells. Also, NE 52-QQ57 ameliorated IL-33-induced oxidative stress by reducing mitochondrial reactive oxygen species and 4-hydroxynonenal. Mechanistically, NE 52-QQ57 mitigated IL-33-induced activation of the p38/nuclear factor-κB signaling pathway. We conclude that targeting GPR4 might be a promising strategy for RA treatment.


Subject(s)
Arthritis, Rheumatoid , Synoviocytes , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Fibroblasts/metabolism , Humans , Interleukin-33/metabolism , Interleukin-33/pharmacology , Mast Cells/metabolism , Mast Cells/pathology , Matrix Metalloproteinase 2/metabolism , NF-kappa B/metabolism , Synoviocytes/metabolism , Tumor Necrosis Factor-alpha/metabolism
7.
Materials (Basel) ; 15(3)2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35161101

ABSTRACT

Traditionally, the discovery of new materials has often depended on scholars' computational and experimental experience. The traditional trial-and-error methods require many resources and computing time. Due to new materials' properties becoming more complex, it is difficult to predict and identify new materials only by general knowledge and experience. Material prediction tools based on machine learning (ML) have been successfully applied to various materials fields; they are beneficial for modeling and accelerating the prediction process for materials that cannot be accurately predicted. However, the obstacles of disciplinary span led to many scholars in materials not having complete knowledge of data-driven materials science methods. This paper provides an overview of the general process of ML applied to materials prediction and uses solid-state electrolytes (SSE) as an example. Recent approaches and specific applications to ML in the materials field and the requirements for building ML models for predicting lithium SSE are reviewed. Finally, some current obstacles to applying ML in materials prediction and prospects are described with the expectation that more materials scholars will be aware of the application of ML in materials prediction.

8.
Exploration (Beijing) ; 2(4): 20220059, 2022 Aug.
Article in English | MEDLINE | ID: mdl-37325602

ABSTRACT

Lithium niobate (LN) is a type of multifunctional dielectric and ferroelectric crystal that is widely used in acoustic, optical, and optoelectronic devices. The performance of pure and doped LN strongly depends on various factors, including its composition, microstructure, defects, domain, and homogeneity. The structure and composition homogeneity can affect both the chemical and physical properties of LN crystals, including their density, Curie temperature, refractive index, and piezoelectric and mechanical properties. In terms of practical demands, both the composition and microstructure characterizations these crystals must range from the nanometer scale up to the millimeter and wafer scales. Therefore, LN crystals require different characterization technologies when verifying their quality for various device applications. Optical, electrical, and acoustic technologies have been developed, including x-ray diffraction, Raman spectroscopy, electron microscopy, and interferometry. To obtain detailed structural information, advanced sub-nanometer technologies are required. For general industrial demands, fast and non-destructive technologies are preferable. This review outlines the advanced methods used to characterize both the composition and homogeneity of LN melts and crystals from the micro- to wafer scale.

9.
Molecules ; 26(22)2021 Nov 22.
Article in English | MEDLINE | ID: mdl-34834135

ABSTRACT

Lithium niobate (LiNbO3) crystals are important dielectric and ferroelectric materials, which are widely used in acoustics, optic, and optoelectrical devices. The physical and chemical properties of LiNbO3 are dependent on microstructures, defects, compositions, and dimensions. In this review, we first discussed the crystal and defect structures of LiNbO3, then the crystallization of LiNbO3 single crystal, and the measuring methods of Li content were introduced to reveal reason of growing congruent LiNbO3 and variable Li/Nb ratios. Afterwards, this review provides a summary about traditional and non-traditional applications of LiNbO3 crystals. The development of rare earth doped LiNbO3 used in illumination, and fluorescence temperature sensing was reviewed. In addition to radio-frequency applications, surface acoustic wave devices applied in high temperature sensor and solid-state physics were discussed. Thanks to its properties of spontaneous ferroelectric polarization, and high chemical stability, LiNbO3 crystals showed enhanced performances in photoelectric detection, electrocatalysis, and battery. Furthermore, domain engineering, memristors, sensors, and harvesters with the use of LiNbO3 crystals were formulated. The review is concluded with an outlook of challenges and potential payoff for finding novel LiNbO3 applications.

10.
J Clin Neurosci ; 90: 118-123, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34275534

ABSTRACT

Few studies have examined the long-term prognosis of Chinese patients with intracerebral hemorrhage (ICH). This study assessed the clinical characteristics and predictors of vascular events occurring within 5 years after ICH. We included consecutive patients diagnosed with first-ever ICH between June 2013 and December 2014. Based on follow-up data (collected until December 2019), we used multivariable logistic regression to examine the clinical characteristics and long-term predictors of vascular events (including recurrent ICH, ischemic stroke, and acute coronary syndrome) in patients who survived more than 30 days after ICH. Across the 307 patients in our analysis, the 5-year mortality rate was 28.01%. Within 5 years after ICH, major vascular events were observed in 62 patients (17.82%, 95% CI 13.78-21.82%). We observed high incidence of recurrent ICH (8.91%) and ischemic stroke (10.06%), but low incidence of acute coronary syndrome (1.15%). Most cases of recurrent ICH (80.65%) occurred within 3 years after ICH. Age ≥56 years and history of ischemic stroke or transient ischemic attack (TIA) were identified as predictors of cardiovascular and cerebrovascular events. ICH survivors are at high risk of both cardiovascular and cerebrovascular events, especially older patients (≥56 years) and those who experienced ischemic stroke or TIA prior to their first ICH. Recurrent ICH is more likely to occur within the first three years after first ICH than at later times. Clinicians should monitor patients closely for adverse events, particularly during the first three years after initial ICH.


Subject(s)
Cerebral Hemorrhage/complications , Ischemic Attack, Transient/etiology , Ischemic Stroke/etiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Incidence , Ischemic Attack, Transient/epidemiology , Ischemic Stroke/epidemiology , Male , Middle Aged , Prognosis , Recurrence , Risk Factors , Survivors , Young Adult
11.
ACS Appl Mater Interfaces ; 13(28): 33262-33271, 2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34213896

ABSTRACT

Natrium superionic conductor (NASICON) solid electrolyte has been attracting wide attention due to its high ionic conductivity, low cost, and environmental friendliness. In this work, the chemical stability of the NASICON solid electrolyte with the composition of Na3Zr2Si2PO12 was evaluated in acidic solutions with different pH values, and the corrosion mechanism of the NASICON solid electrolyte was revealed at the multiscale level. Variations in bulk impedance, grain boundary impedance, and surface crack impedance with immersion time were determined by an AC impedance method. Comprehensive studies upon scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) etching, X-ray diffraction (XRD), and Raman spectroscopy, the morphological transformation, degradation limit depth, Cl- penetration effect, and proton exchange between H3O+ and Na+ were examined ranging from macro- and meso- to microscales, respectively. With the decrease of the pH of the solution, the exchange rate between H3O+ and Na+ protons increases. The lack of Na+ within the crystallographic lattice leads to the shrinkage of phosphorus-oxygen tetrahedra, which is the main reason for the decrease of unit cell volume, grain refinement, and surface cracks gradually. This work features multiscale characterizations of crystal structure, grain boundaries, surface morphology changes, and Na+ transport, which deepens our physicochemical understanding of solid electrolytes with high chemical stability.

13.
Materials (Basel) ; 14(3)2021 Jan 21.
Article in English | MEDLINE | ID: mdl-33494325

ABSTRACT

Nanoscale engineering of regular structured materials is immensely demanded in various scientific areas. In this work, vertically oriented TiO2 nanotube arrays were grown by self-organizing electrochemical anodization. The effects of different fluoride ion concentrations (0.2 and 0.5 wt% NH4F) and different anodization times (2, 5, 10 and 20 h) on the morphology of nanotubes were systematically studied in an organic electrolyte (glycol). The growth mechanisms of amorphous and anatase TiO2 nanotubes were also studied. Under optimized conditions, we obtained TiO2 nanotubes with tube diameters of 70-160 nm and tube lengths of 6.5-45 µm. Serving as free-standing and binder-free electrodes, the kinetic, capacity, and stability performances of TiO2 nanotubes were tested as lithium-ion battery anodes. This work provides a facile strategy for constructing self-organized materials with optimized functionalities for applications.

14.
Front Chem ; 9: 807500, 2021.
Article in English | MEDLINE | ID: mdl-35087793

ABSTRACT

The rapid development of portable, wearable, and implantable electronic devices greatly stimulated the urgent demand for modern society for multifunctional and miniaturized electrochemical energy storage devices and their integrated microsystems. This article reviews material design and manufacturing technology in different micro-supercapacitors (MSCs) along with devices integrate to achieve the targets of their various applications in recent years. Finally, We also critically prospect the future development directions and challenges of MSCs.

15.
Onco Targets Ther ; 13: 3117-3128, 2020.
Article in English | MEDLINE | ID: mdl-32346295

ABSTRACT

BACKGROUND: Increasing evidence has demonstrated the importance of non-coding RNAs including long non-coding RNA (lncRNA) and microRNAs (miRNAs) in the tumorigenesis of osteosarcoma (OS). Abnormal expression of lncRNA olfactory receptor family 3 subfamily A member 4 (OR3A4) was found in multiple human cancers; however, the function of OR3A4 in OS remains largely unknown. MATERIALS AND METHODS: The expression level of OR3A4 in OS tissues and cell lines was detected by RT-qPCR. Cell counting kit-8 assay, colony formation and flow cytometry analysis were performed to determine the growth of OS cells. The targets of OR3A4 were predicted using the miRDB database. The binding between OR3A4 and miRNAs was confirmed by dual-luciferase reporter assay. RESULTS: OR3A4 was overexpressed in OS tissues and correlated with the advanced progression of OS patients. Down-regulation of OR3A4 significantly inhibited the proliferation and colony formation of OS cells. Mechanistically, OR3A4 acted as a sponge of miR-1207-5p. Glucose-6-phosphate dehydrogenase (G6PD) was identified as a target of miR-1207-5p. Knockdown of OR3A4 increased the expression of miR-1207-5p and consequently, suppressed the level of G6PD in OS cells. Due to the essential role of G6PD in the pentose phosphate pathway (PPP), depletion of OR3A4 inhibited NADPH production, glucose consumption and lactate generation. Decreased level of NADPH by depletion of OR3A4 up-regulated the redox state (ROS) content and resulted in endoplasmic reticulum (ER) stress in OS cells. Restoration of G6PD significantly attenuated the cell growth inhibition induced by OR3A4 knockdown. CONCLUSION: Our finding suggested the critical role of OR3A4 in the proliferation of OS cells via targeting the miR-1207-5p/G6PD axis.

16.
Dalton Trans ; 49(6): 1811-1821, 2020 Feb 11.
Article in English | MEDLINE | ID: mdl-31960854

ABSTRACT

Efficient and low-cost bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are of vital importance in energy conversion. Herein, an excellent highly dispersed Co nanoparticle decorated N-doped defective carbon nano-framework (Co-N-C) derived from a ZnCo bimetal organic framework (bi-MOF) is reported. A high specific surface area originating from zinc evaporation facilitates the adsorption and desorption of oxygen, which promotes the accessibility of catalytic sites. The abundant Co-N-C species act as strong bridging bonds between Co nanoparticles and carbon materials which facilitate interfacial electron transfer. Co-N-C-0.5 (0.5 represents the molar ratio of Zn in the initial ZIF-67) exhibits a low overpotential gap of 0.94 V due to the number of active sites (e.g. N-doped defective carbon and the CoNx/Co composite) and fast interfacial electron transfer. In addition, a hybrid Na-air battery with the Co-N-C-0.5 material displays a low voltage gap of 0.31 V and a high round-trip efficiency of 90.0% at a current density of 0.1 mA cm-2. More importantly, the hybrid Na-air battery shows fantastic cyclability for charging and discharging due to its stable structure. Our results confirm Co-N-C materials derived from a bi-MOF as alternatives to high-cost Pt/C catalysts for ORR and OER activities in metal-air batteries.

17.
Dalton Trans ; 49(4): 1107-1115, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31894213

ABSTRACT

Electrochemical energy storage performance of inorganic solid materials is highly dependent on the number of electroactive sites and their reactivity. However, it is difficult to control the number of electroactive sites and their reactivity during the solid crystallization process. Herein, we synthesized novel poorly crystalline La3+:Ni-Cl oxyhydroxide gels with sufficient electroactive sites and atomically homogeneous distribution of Ni2+, La3+, and Cl- ions. Their poorly crystalline structure may favor fast ion diffusion and Cl- ions help in the formation of electroactive sites, while La3+ ions enhance the ionic conductivity within these electrode materials. Used as positive materials for hybrid supercapacitors, La3+:Ni-Cl oxyhydroxide gels showed a high specific capacity of 203 mA h g-1, a value higher than most reported values of Ni(OH)2-based materials. This work represents a new strategy for the synthesis of new electrode materials with high capacity and fast ion diffusion kinetics.

18.
Nanotechnology ; 31(2): 024002, 2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31557733

ABSTRACT

Advances in renewable and sustainable energy technologies critically depend on our ability to rationally design and process target materials with optimized performances. Advanced material design and discovery are ideally involved in material prediction, synthesis and characterization. Control of material crystallization enables the rational design and discovery of novel functional inorganic materials in multi-scale. Material processing can be adjusted by various physical fields and chemical effects at different energy states. Material microstructure, architecture and functionality can thus be modified by multiple design methodologies. In this review, we show typical examples using physical and chemical methods to shape inorganic functional materials and evaluate their specific applications in Na-air batteries, Li-ion batteries and supercapacitors. Furthermore, this review also provides insight into the understanding of synthesis-structure relationship of inorganic functional materials.

19.
Nanotechnology ; 31(13): 132003, 2020 Mar 27.
Article in English | MEDLINE | ID: mdl-31770742

ABSTRACT

NASICON-type (lithium super ionic conductor) solid electrolyte is of great interest because of its high ionic conductivity, wide potential window, and good chemical stability. In this paper, the key problems and challenges of NASICON-type solid electrolyte are described from the aspects of ionic conductivity, electrode interface, and electrochemical stability. Firstly, the migration mechanism of lithium ion is analyzed from the three-dimensional structure of NASICON-type solid electrolyte, and progress in the research of conductivity and stability is summarized. Then, the effective methods to reduce interface impedance and improve the cycle stability of all-solid-state lithium batteries (ASSLBs) with NASICON-type solid electrolyte are introduced. Finally, solutions to improve the conductivity of electrolytes and deal with electrode/electrolyte interface problems are summarized, and the development prospects of ASSLBs are discussed.

20.
Nanomaterials (Basel) ; 8(7)2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29966399

ABSTRACT

Porous α-Fe2O3 nanowire arrays coated with a layer of carbon shell have been prepared by a simple hydrothermal route. The as-synthesized products show an excellent electrochemical performance with high specific capacitance and good cycling life after 9000 cycles. A solid state asymmetric supercapacitor (ASC) with a 2 V operation voltage window has been assembled by porous α-Fe2O3/C nanowire arrays as the anode materials, and MnO2 nanosheets as the cathode materials, which gives rise to a maximum energy density of 30.625 Wh kg−1and a maximum power density of 5000 W kg−1 with an excellent cycling performance of 82% retention after 10,000 cycles.

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