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1.
Angew Chem Int Ed Engl ; : e202403585, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565432

RESUMEN

In spite of the competitive performance at room temperature, the development of sodium-ion batteries (SIBs) is still hindered by sluggish electrochemical reaction kinetics and unstable electrode/electrolyte interphase under subzero environments. Herein, a low-concentration electrolyte, consisting of 0.5M NaPF6 dissolving in diethylene glycol dimethyl ether solvent, is proposed for SIBs working at low temperature. Such an electrolyte generates a thin, amorphous, and homogeneous cathode/electrolyte interphase at low temperature. The interphase is monolithic and rich in organic components, reducing the limitation of Na+ migration through inorganic crystals, thereby facilitating the interfacial Na+ dynamics at low temperature. Furthermore, it effectively blocks the unfavorable side reactions between active materials and electrolytes, improving the structural stability. Consequently, Na0.7Li0.03Mg0.03Ni0.27Mn0.6Ti0.07O2//Na and hard carbon//Na cells deliver a high capacity retention of 90.8 % after 900 cycles at 1C, a capacity over 310 mAh g-1 under -30 °C, respectively, showing long-term cycling stability and great rate capability at low temperature.

2.
Nanomicro Lett ; 16(1): 145, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441811

RESUMEN

Aqueous Zn-ion batteries (AZIBs) have attracted increasing attention in next-generation energy storage systems due to their high safety and economic. Unfortunately, the side reactions, dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion batteries. Here, we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a "catcher" to arrest active molecules (bound water molecules). The stable solvation structure of [Zn(H2O)6]2+ is capable of maintaining and completely inhibiting free water molecules. When [Zn(H2O)6]2+ is partially desolvated in the Helmholtz outer layer, the separated active molecules will be arrested by the "catcher" formed by the strong hydrogen bond N-H bond, ensuring the stable desolvation of Zn2+. The Zn||Zn symmetric battery can stably cycle for 2250 h at 1 mAh cm-2, Zn||V6O13 full battery achieved a capacity retention rate of 99.2% after 10,000 cycles at 10 A g-1. This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs.

3.
Neural Netw ; 143: 595-606, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34343774

RESUMEN

The essential problem of multi-view spectral clustering is to learn a good common representation by effectively utilizing multi-view information. A popular strategy for improving the quality of the common representation is utilizing global and local information jointly. Most existing methods capture local manifold information by graph regularization. However, once local graphs are constructed, they do not change during the whole optimization process. This may lead to a degenerated common representation in the case of existing unreliable graphs. To address this problem, rather than directly using fixed local representations, we propose a dynamic strategy to construct a common local representation. Then, we impose a fusion term to maximize the common structure of the local and global representations so that they can boost each other in a mutually reinforcing manner. With this fusion term, we integrate local and global representation learning in a unified framework and design an alternative iteration based optimization procedure to solve it. Extensive experiments conducted on a number of benchmark datasets support the superiority of our algorithm over several state-of-the-art methods.


Asunto(s)
Algoritmos , Benchmarking , Análisis por Conglomerados , Aprendizaje
4.
Dalton Trans ; 42(37): 13635-41, 2013 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-23900234

RESUMEN

A new ternary selenostannate Ba6Sn6Se13 has been synthesized by a high temperature solid-state method. The compound crystallizes in the non-centrosymmetric orthorhombic space group P2(1)2(1)2(1) and may be represented as Ba6Sn5(2+)Sn(4+)Se13 with mixed valence Sn atoms. Sn(4+) cations lie in a tetrahedral environment, while Sn(2+) cations are found in two kinds of coordination environments: the trigonal pyramid and quadrangular pyramid. SnSe(n) (n = 3, 4, 5) polyhedra are further connected to generate a three-dimensional framework with Ba(2+) residing in cavities. Ba6Sn6Se13 shows moderate nonlinear optical response and is the first reported NLO compound in the Ba-Sn-Se system. In addition, diffuse reflectance spectroscopy measurement indicates that the band gap of Ba6Sn6Se13 is 1.52(2) eV and thermal analysis suggests that the compound melts incongruently. The theoretically calculated SHG response and band gap are in good agreement with experimental results.

5.
Inorg Chem ; 51(21): 11736-44, 2012 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-23046251

RESUMEN

The 12 new rare-earth tellurides Ba(2)MLnTe(5) (M = Ga and Ln = Sm, Gd, Dy, Er, Y; M = In and Ln = Ce, Nd, Sm, Gd, Dy, Er, Y) have been synthesized by solid-state reactions. The two compounds Ba(2)GaLnTe(5) (Ln = Sm, Gd) are isostructural and crystallize in the centrosymmetric space group P1, while the other 10 compounds belong to another structure type in the noncentrosymmetric space group Cmc2(1). In both structure types, there are one-dimensional anionic (1)(∞)[MLnTe(5)](4-) chains built from LnTe(6) octahedra and MTe(4) (M = Ga, In) tetrahedra, but the connectivity between the LnTe(6) octahedra and MTe(4) tetrahedra is different for the two structure types. On the basis of the diffuse-reflectance spectra, the band gaps are around 1.1-1.3 eV for these compounds. The Ba(2)MLnTe(5) (M = Ga and Ln = Gd, Dy; M = In and Ln = Gd, Dy, Er) compounds are paramagnetic and obey the Curie-Weiss law, while the magnetic susceptibility of Ba(2)InSmTe(5) deviates from the Curie-Weiss law. In addition, electronic structure calculation on Ba(2)MYTe(5) (M = Ga, In) indicates that they are both direct-gap semiconductors with large nonlinear-optical coefficients.

6.
Inorg Chem ; 51(12): 6860-7, 2012 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-22671989

RESUMEN

The twelve quaternary rare-earth selenides Ba(2)MLnSe5 (M = Ga, In; Ln = Y, Nd, Sm, Gd, Dy, Er) have been synthesized for the first time. The compounds Ba(2)GaLnSe(5) (Ln = Y, Nd, Sm, Gd, Dy, Er) are isostructural and crystallize in a new structure type in the centrosymmetric space group P ̅1 of the triclinic system while the isostructural compounds Ba(2)InLnSe(5) (Ln = Y, Nd, Sm, Gd, Dy, Er) belong to the Ba(2)BiInS(5) structure type and crystallize in the noncentrosymmetric space group Cmc2(1) of the orthorhombic system. The structures contain infinite one-dimensional anionic chains (1)(∞)[GaLnSe(5)](4-) and (1)(∞)[InLnSe(5)](4-), and both chains are built from LnSe(6) octahedra and MSe(4) (M = Ga, In) tetrahedra in the corresponding selenides. As deduced from the diffuse reflectance spectra, the band gaps of most Ba(2)MLnSe(5) (M = Ga, In; Ln = Y, Nd, Sm, Gd, Dy, Er) compounds are around 2.2 eV. The magnetic susceptibility measurements on Ba(2)GaGdSe(5) and Ba(2)InLnSe(5) (Ln = Nd, Gd, Dy, Er) indicate that they are paramagnetic and obey the Curie-Weiss law, while the magnetic susceptibility of Ba(2)InSmSe(5) deviates from the Curie-Weiss law as a result of the crystal field splitting. Furthermore, Ba(2)InYSe(5) exhibits a strong second harmonic generation response close to that of AgGaSe(2), when probed with the 2090 nm laser as fundamental wavelength.

7.
Inorg Chem ; 51(10): 5839-43, 2012 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-22559208

RESUMEN

The four isostructural compounds Li(2)In(2)MQ(6) (M = Si, Ge; Q = S, Se) have been synthesized for the first time. They crystallize in the noncentrosymmetric monoclinic space group Cc with the three-dimensional framework composed of corner-sharing LiQ(4), InQ(4), and MQ(4) tetrahedra. The second-harmonic-generation signal intensities of the two sulfides and two selenides were close to those of AgGaS(2) and AgGaSe(2), respectively, when probed with a laser with 2090 nm as the fundamental wavelength. They possess large band gaps of 3.61(2) eV for Li(2)In(2)SiS(6), 3.45(2) eV for Li(2)In(2)GeS(6), 2.54(2) eV for Li(2)In(2)SiSe(6), and 2.30(2) eV for Li(2)In(2)GeSe(6), respectively. Moreover, these four compounds all melt congruently at relatively low temperatures, which makes it feasible to grow bulk crystals needed for practical application by the Bridgman-Stockbarger method.

8.
Neurochem Int ; 58(8): 904-13, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21349309

RESUMEN

The etiology and pathophysiology of depression remain unknown. Previous works were mostly performed on single observation time-point which might be insufficiently to reveal the molecular events changed during the disease development. Adult BALB/c mice were exposed to unpredictable chronic mild stress (UCMS) for different periods and differential 2D gel electrophoresis (DIGE) approach was employed to the brain tissue to explore the molecular disease signatures. Sustained elevation of corticosterone level was observed, suggesting the hyperactivity of hypothalamic-pituitary-adrenal (HPA) axis when the mice were subjected to the stressful situation. The behavioral results indicated the depressive alterations of the mice exposing to UCMS. The altered proteins identified by proteomics showed that abnormal energy mobilization under stress condition was accompanied by overproduction of reactive oxygen species (ROS) and endoplasmic reticulum (ER) stress. Cytoskeleton protein and anti-oxidant enzymes were also changed by UCMS treatment. The results of biochemical and immunohistochemical assay confirmed the changes identified by DIGE analysis. These results indicated that the insufficiency of ATP synthesis, overwhelming ROS production and ER stress subsequently contributed to the cytoskeletal damage and inhibition to expression of some anti-oxidant proteins, which might ultimately bring functional neuron to apoptosis or death. Proteins whose expression is affected may provide tools for potential treatment strategies.


Asunto(s)
Encéfalo/fisiología , Trastorno Depresivo/metabolismo , Trastorno Depresivo/terapia , Proteómica/métodos , Estrés Psicológico/metabolismo , Estrés Psicológico/terapia , Animales , Enfermedad Crónica , Trastorno Depresivo/genética , Metabolismo Energético/genética , Predicción , Masculino , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo/genética , Análisis por Matrices de Proteínas/métodos , Distribución Aleatoria , Estrés Psicológico/genética
9.
Sci China Life Sci ; 53(12): 1428-32, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21181344

RESUMEN

The aim of this study was to investigate the role of endogenous enkephalin in the cerebral antihyperalgesic action of gabapentin. Neuropathic pain models and antihyperalgesic effect of gabapentin were confirmed by the presentation and changes of mechanical allodynia and thermal hyperalgesia of operated mouse hind paws. The results suggested that endogenous enkephalin may not be involved in the antihyperalgesic effect of gabapentin.


Asunto(s)
Aminas/farmacología , Aminas/uso terapéutico , Corteza Cerebral/efectos de los fármacos , Ácidos Ciclohexanocarboxílicos/farmacología , Ácidos Ciclohexanocarboxílicos/uso terapéutico , Encefalinas/metabolismo , Antagonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Hiperalgesia/tratamiento farmacológico , Ácido gamma-Aminobutírico/farmacología , Ácido gamma-Aminobutírico/uso terapéutico , Aminas/metabolismo , Animales , Corteza Cerebral/fisiología , Ácidos Ciclohexanocarboxílicos/metabolismo , Encefalinas/genética , Antagonistas de Aminoácidos Excitadores/metabolismo , Gabapentina , Hiperalgesia/fisiopatología , Masculino , Ratones , Ratones Endogámicos BALB C , Dimensión del Dolor , Ácido gamma-Aminobutírico/metabolismo
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