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1.
J Colloid Interface Sci ; 675: 251-262, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38970911

RESUMEN

Li-rich Mn-based (LMR) layered oxides are considered promising cathode materials for high energy-density Li-ion batteries. Nevertheless, challenges such as irreversible oxygen loss at the surface during the initial charge, alteration of the bulk structure, and poor rate performance impede their path to commercialisation. Most modification methods focus on specific layers, making the overall impact of modifications at various depths on the properties of materials unclear. This research presents an approach by using doping to adjust both surface and bulk properties; the materials with surface and bulk fluoride anion doping are synthesised to explore the connection between doping depth, structural and electrochemical stability. The surface-doped material significantly improves the initial Coulombic efficiency (ICE) from 77.85% to 85.12% and limits phase transitions, yet it does not enhance rate performance. Conversely, doping in bulk stands out by improving both rate performance and cyclic stability: it increases the specific discharge capacity by around 60 mAh g-1 and enhances capacity retention from 57.69% to 82.26% after 300 cycles at 5C. These results highlight a notable dependence of material properties on depth, providing essential insights into the mechanisms of surface and bulk modifications.

2.
Adv Sci (Weinh) ; 11(30): e2404307, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38874109

RESUMEN

Constructing composite solid electrolytes (CSEs) integrating the merits of inorganic and organic components is a promising approach to developing high-performance all-solid-state lithium metal batteries (ASSLMBs). CSEs are now capable of achieving homogeneous and fast Li-ion flux, but how to escape the trade-off between mechanical modulus and adhesion is still a challenge. Herein, a strategy to address this issue is proposed, that is, intercalating highly conductive, homogeneous, and viscous-fluid ionic conductors into robust coordination laminar framework to construct laminar solid electrolyte with homogeneous and fast Li-ion conduction (LSE-HFC). A 9 µm-thick LSH-HFC, in which poly(ethylene oxide)/succinonitrile is adsorbed by coordination laminar framework with metal-organic framework nanosheets as building blocks, is used here as an example to determine the validity. The Li-ion transfer mechanism is verified and works across the entire LSE-HFC, which facilitates homogeneous Li-ion flux and low migration energy barriers, endowing LSE-HFC with high ionic conductivity of 5.62 × 10-4 S cm-1 and Li-ion transference number of 0.78 at 25 °C. Combining the outstanding mechanical strength against punctures and the enhanced adhesion force with electrodes, LSE-HFC harvests uniform Li plating/stripping behavior. These enable the realization of high-energy-density ASSLMBs with excellent cycling stability when being assembled as LiFePO4/Li and LiNi0.6Mn0.2Co0.2O2/Li cells.

3.
Fish Shellfish Immunol ; 146: 109426, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38316349

RESUMEN

Glutathione S-transferase P1 (GSTP1), the most ubiquitous member of the GST superfamily, plays vital roles in the detoxification, antioxidant defense, and modulation of inflammatory responses. However, limited studies have been conducted on the function of GSTP1 in antiviral innate immunity. In this study, we have cloned the homolog of GSTP1 in triploid hybrid crucian carp (3nGSTP1) and investigated its regulatory role in the interferon signaling pathway. The open reading frame of 3nGSTP1 is composed of 627 nucleotides, encoding 209 amino acids. In response to spring viremia of carp virus (SVCV) infection, the mRNA level of 3nGSTP1 was up-regulated in the liver, kidney, and caudal fin cell lines (3 nF C) of triploid fish. The knockdown of 3nGSTP1 in 3 nF C improved host cell's antiviral capacity and attenuated SVCV replication. Additionally, overexpression of 3nGSTP1 inhibited the activation of IFN promoters induced by SVCV infection, poly (I:C) stimulation, or the RLR signaling factors. The co-immunoprecipitation assays further revealed that 3nGSTP1 interacts with 3nMAVS. In addition, 3nGSTP1 dose-dependently inhibited 3nMAVS-mediated antiviral activity and reduced 3nMAVS protein level. Mechanistically, 3nGSTP1 promoted ubiquitin-proteasome degradation of MAVS by promoting its K48-linked polyubiquitination. To conclude, our results indicate that GSTP1 acts as a novel inhibitor of MAVS, which negatively regulates the IFN signaling.


Asunto(s)
Carpas , Enfermedades de los Peces , Infecciones por Rhabdoviridae , Rhabdoviridae , Animales , Triploidía , Transducción de Señal , Rhabdoviridae/fisiología , Infecciones por Rhabdoviridae/veterinaria , Inmunidad Innata/genética , Poli I-C/farmacología , Antivirales
4.
Entropy (Basel) ; 25(7)2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37510005

RESUMEN

Machine learning has become increasingly popular in academic and industrial communities and has been widely implemented in various online applications due to its powerful ability to analyze and use data. Among all the machine learning models, decision tree models stand out due to their great interpretability and simplicity, and have been implemented in cloud computing services for various purposes. Despite its great success, the integrity issue of online decision tree prediction is a growing concern. The correctness and consistency of decision tree predictions in cloud computing systems need more security guarantees since verifying the correctness of the model prediction remains challenging. Meanwhile, blockchain has a promising prospect in two-party machine learning services as the immutable and traceable characteristics satisfy the verifiable settings in machine learning services. In this paper, we initiate the study of decision tree prediction services on blockchain systems and propose VDT, a Verifiable Decision Tree prediction scheme for decision tree prediction. Specifically, by leveraging the Merkle tree and hash function, the scheme allows the service provider to generate a verification proof to convince the client that the output of the decision tree prediction is correctly computed on a particular data sample. It is further extended to an update method for a verifiable decision tree to modify the decision tree model efficiently. We prove the security of the proposed VDT schemes and evaluate their performance using real datasets. Experimental evaluations show that our scheme requires less than one second to produce verifiable proof.

5.
ChemSusChem ; 12(10): 2294-2301, 2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-30806010

RESUMEN

Layered lithium-rich cathode materials are one of the most promising cathode materials owing to their higher mass energy density than the commercial counterparts. A series of trace Yb-doped lithium-rich cathode materials Li1.2 Mn0.54 Ni0.13 Co0.13-x Ybx O2 (0≤x≤0.050) were synthesized and the effects were investigated by XRD, X-ray photoelectron spectroscopy, and high-resolution TEM. The participation of Yb ions in electrochemical reactions and the larger binding energy of Yb-O than M-O (M=Mn, Ni, Co), which expands the lithium layer spacing and stabilizes the oxygen stacking, resulted in excellent performance of materials doped with a limited Yb content (x≤0.005). However, higher doping amounts (x>0.005) significantly increased the charge-transfer impedance and led to a sharp deterioration in electrochemical performance. The reason lies in the large difference in ionic radius between the transition metals (Mn, Co, and Ni) and Yb. There is an upper limit to the amount of Yb ions in the lattice. If the amount of Yb is higher than the limit, excess Yb ions enter the Li layers instead of staying in the transition-metal layers or even segregate on the surface and form electrochemically inert oxides.

6.
Adv Mater ; 29(6)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27911034

RESUMEN

A novel carbon structure, highly branched homogeneous-N-doped graphitic (BNG) tubular foam, is designed via a novel N, N-dimethylformamide (DMF)-mediated chemical vapor deposition method. More structural defects are found at the branched portions as compared with the flat tube domains providing abundant active sites and spacious reservoirs for Li+ storage. An individual BNG branch nanobattery is constructed and tested using in situ transmission electron microscopy and the lithiation process is directly visualized in real time.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(9): 2314-7, 2012 Sep.
Artículo en Chino | MEDLINE | ID: mdl-23240386

RESUMEN

As a kind of new electric light source, electrodeless discharge lamps (EDL) are based on high-frequency electromagnetic induction and nonpolar gas discharge. Visible light is emitted as a result of Hg 253.7 nm resonance spectrum line inspiring phosphor. The influence of indium net position on the Hg 253. 7 nm resonance spectral line was studied experimentally by atomic emission spectral analysis. It was found that the relative intensity of Hg 253.7 nm resonance spectral line is strongest when the indium net is located at both ends of coupling coil, weaker at middle and weakest when far away from coupling coil. It was inferred that there is an optimum indium net position for EDL, and the corresponding lighting effect is maximal. The results were qualitatively analyzed from the standpoint of gas discharge theory, combined with the finite element simulation of Maxwell 3D, which has instructive value for pattern design and parametric optimization of EDL.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 50-2, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22497125

RESUMEN

As a kind of new electric light source, electrodeless discharge lamps are of long life, low mercury and non-stroboscopic light. The lighting effect of electrodeless discharge lamps depends on the radiation efficiency of 253.7 nm resonance spectra line to a large extent. The influence of cold temperature on 253.7 nm resonance spectra line has been studied experimentally by atomic emission spectral analysis. It was found that the radiation efficiency of 253.7 nm resonance spectra line is distributed in a nearly normal fashion with the variation of cold spot temperature, in other words, there is an optimum cold spot temperature for an electrodeless discharge lamp. At last, the results of experiments were analyzed through gas discharge theory, which offers guidance to the improvement of lighting effect for electrodeless discharge lamps.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(9): 2533-5, 2011 Sep.
Artículo en Chino | MEDLINE | ID: mdl-22097865

RESUMEN

Electrodeless lamp in pear shape was ignited using inductively coupled discharge setup and Ar-Hg mixtures as working gas. The changes in electronic temperature and density with axial and radial positions at 5 s of igniting were studied by means of emission spectrometry. The changes in electronic temperature were obtained according to the Ar line intensity ratio of 425.9 nm/ 750.4 nm. And the variations in electronic density were analyzed using 750.4 nm line intensity. It was found that plasma electronic temperature and density is various at different axial or radial positions. The electronic temperatures first increase, then decrease, and then increase quickly, and finally decline. While the electronic density firstly increase quickly, the decrease, and then rise slowly and finally decline again with axial distance increasing. With radial distance increasing, electronic temperature increases to a stable area, then continues to rise, while electronic density decreases.

10.
Molecules ; 11(12): 1009-14, 2006 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-18007405

RESUMEN

A new neolignan glycoside, (7R,8R)-7,8-dihydro-9'-hydroxyl-3'-methoxyl- 8-hydroxymethyl-7-(4-hydroxy-3-methoxyphenyl)-1'-benzofuranpropanol 9'-O-beta-D- glucopyranoside (1) was isolated from the leaves of Acer truncatum along with (7R,8R)-7,8-dihydro-9'-hydroxyl-3'-methoxyl-8-hydroxymethyl-7-(4-O-alpha-L-rhamno- pyranosyloxy-3-methoxyphenyl)-1'-benzofuranpropanol (2), schizandriside (3), lyoniresinol (4), berchemol (5), (-)-pinoresinol-4-O-beta-D-glucopyranoside (6), hecogenin (7), chlorogenic acid (8) and neochlorogenic acid (9). Their structures were elucidated on the basis of extensive spectroscopic data. The absolute configuration of compounds 1 was established by its CD spectrum. The antibacterial activities of compounds 1-7 were evaluated.


Asunto(s)
Acer/química , Glicósidos/aislamiento & purificación , Lignanos/aislamiento & purificación , Hojas de la Planta/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Isótopos de Carbono , Glicósidos/química , Glicósidos/farmacología , Lignanos/química , Lignanos/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Protones
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