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1.
Small ; 18(48): e2204912, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36266964

RESUMO

The electrochemical conversion reaction, usually featured by multiple redox processes and high specific capacity, holds great promise in developing high-energy rechargeable battery technologies. However, the complete structural change accompanied by spontaneous atomic migration and volume variation during the charge/discharge cycle leads to electrode disintegration and performance degradation, therefore severely restricting the application of conventional conversion-type electrodes. Herein, latticed-confined conversion chemistry is proposed, where the "intercalation-like" redox behavior is realized on the electrode with a "conversion-like" high capacity. By delicately formulating the high-entropy compounds, the pristine crystal structure can be preserved by the inert lattice framework, thus enabling an ultra-high initial Coulombic efficiency of 92.5% and a long cycling lifespan over a thousand cycles after the quasistatic charge-discharge cycle. This lattice-confined conversion chemistry unfolds a ubiquitous insight into the localized redox reaction and sheds light on developing high-performance electrodes toward next-generation high-energy rechargeable batteries.


Assuntos
Líquidos Corporais , Fontes de Energia Elétrica , Eletrodos , Entropia
2.
Small ; 17(37): e2101137, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331406

RESUMO

The past decade has witnessed a rapidly growing interest toward sodium ion battery (SIB) for large-scale energy storage in view of the abundance and easy accessibility of sodium resources. Key to addressing the remaining challenges and setbacks and to translate lab science into commercializable products is the development of high-performance anode materials. Anode materials featuring combined conversion and alloying mechanisms are one of the most attractive candidates, due to their high theoretical capacities and relatively low working voltages. The current understanding of sodium-storage mechanisms in conversion-alloying anode materials is presented here. The challenges faced by these materials in SIBs, and the corresponding improvement strategies, are comprehensively discussed in correlation with the resulting electrochemical behavior. Finally, with the guidance and perspectives, a roadmap toward the development of advanced conversion-alloying materials for commercializable SIBs is created.


Assuntos
Ligas , Sódio , Eletrodos
3.
ACS Appl Mater Interfaces ; 9(8): 6979-6987, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28103016

RESUMO

Cost-effective sodium ion batteries (SIBs) are emerging as a desirable alternative choice to lithium ion batteries in terms of application in large-scale energy storage devices. SnS2 is regarded as a potential anode material for SIBs because of its unique layered structure and high theoretical specific capacity. However, the development of SnS2 was hindered by the sluggish kinetics of the diffusion process and the inevitable volume change during repeated sodiation-desodiation processes. In this work, SnS2 with a unique nanowall array (NWA) structure is fabricated by one-step pulsed spray evaporation chemical vapor deposition (PSE-CVD), which could be used directly as binder-free and carbon-free anodes for SIBs. The SnS2 NWA electrode achieves a high reversible capacity of 576 mAh g-1 at 500 mA g-1 and enhanced cycling stability. Attractively, an excellent rate capability is demonstrated with ∼370 mAh g-1 at 5 A g-1, corresponding to a capacity retention of 64.2% at 500 mA g-1. The superior sodium storage capability of the SnS2 NWA electrode could be attributed to outstanding electrode design and a rational growth process, which favor fast electron and Na-ion transport, as well as provide steady structure for elongated cycling.

4.
Reprod Sci ; 19(11): 1190-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22581801

RESUMO

This study aimed to analyze the distribution of single-nucleotide polymorphisms (SNPs) of testis-expressed 15 (TEX15) gene in the Chinese Han infertile men and fertile men. This case-control study comprised 309 infertile men with nonobstructive azoospermia (NOA, n = 199) or severe oligozoospermia (SO, n = 110) and 377 fertile controls. Six SNPs were genotyped by Sequenom iplex technology. The results showed that the variants rs323346 and rs323347 contributed to the increasing risk of SO (P = .041, odds ratio [OR] = 1.635, 95% confidence interval [CI] = 1.018-2.628 and P = .046, OR = 1.616, 95% CI = 1.006-2.597). The haplotype AT of the SNPs rs323347 and rs323346 could reduce risk in the patients with SO (P = .040, OR = 0.616, and 95% CI = 0.383-0.990). The haplotype GC of the variants rs323347 and rs323346 conferred a significantly increased risk of SO (P = .040, OR = 1.624, 95% CI = 1.010-2.610). Thus, the polymorphisms rs323346 and rs323347 of the TEX15 gene could be considered the genetic risk factors for spermatogenic failure in the Chinese Han population.


Assuntos
Proteínas de Ciclo Celular/genética , Predisposição Genética para Doença/genética , Infertilidade Masculina/genética , Polimorfismo de Nucleotídeo Único , Espermatogênese/genética , Adulto , Azoospermia/genética , Estudos de Casos e Controles , China , DNA/sangue , Haplótipos/genética , Humanos , Masculino , Oligospermia/genética
5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 25(4): 766-9, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18788276

RESUMO

Independent component analysis (ICA) is a novel method developed in recent years for Blind Source Separation. In this paper, the phonocardiogram (PCG) was separated into three components by applying ICA. The basic principle of ICA was introduced in this paper. A fast and robust fixed-point algorithm for ICA was used to analyze PCG signals in this study. The experiments showed that ICA could separate the components of heart sounds from PCG signals successfully.


Assuntos
Algoritmos , Fonocardiografia/métodos , Análise de Componente Principal , Processamento de Sinais Assistido por Computador , Ruídos Cardíacos , Humanos
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