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1.
J Am Chem Soc ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935530

RESUMO

High-entropy alloy nanoparticles (HEA-NPs) show exceptional properties and great potential as a new generation of functional materials, yet a universal and facile synthetic strategy in air toward nonoxidized and precisely controlled composition remains a huge challenge. Here we provide a laser scribing method to prepare single-phase solid solution HEA-NPs libraries in air with tunable composition at the atomic level, taking advantage of the laser-induced metastable thermodynamics and substrate-assisted confinement effect. The three-dimensional porous graphene substrate functions as a microreactor during the fast heating/cooling process, which is conductive to the generation of the pure alloy phase by effectively blocking the binding of oxygen and metals, but is also beneficial for realizing accurate composition control via microstructure confinement-endowed favorable vapor pressure. Furthermore, by combining an active learning approach based on an adaptive design strategy, we discover an optimal composition of quinary HEA-NP catalysts with an ultralow overpotential for Li-CO2 batteries. This method provides a simple, fast, and universal in-air route toward the controllable synthesis of HEA-NPs, potentially integrated with machine learning to accelerate the research on HEAs.

2.
Am J Physiol Endocrinol Metab ; 326(3): E326-E340, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294696

RESUMO

This study aimed to evaluate the role of skeletal muscle-derived interleukin (IL)-15 in the regulation of skeletal muscle autophagy using IL-15 knockout (KO) and transgenic (TG) mice. Male C57BL/6 wild-type (WT), IL-15 KO, and IL-15 TG mice were used in this study. Changes in muscle mass, forelimb grip strength, succinate dehydrogenase (SDH) activity, gene and protein expression levels of major regulators and indicators of autophagy, comprehensive gene expression, and DNA methylation in the gastrocnemius muscle were analyzed. Enrichment pathway analyses revealed that the pathology of IL-15 gene deficiency was related to the autophagosome pathway. Moreover, although IL-15 KO mice maintained gastrocnemius muscle mass, they exhibited a decrease in autophagy induction. IL-15 TG mice exhibited a decrease in gastrocnemius muscle mass and an increase in forelimb grip strength and SDH activity in skeletal muscle. In the gastrocnemius muscle, the ratio of phosphorylated adenosine monophosphate-activated protein kinase α (AMPKα) to total AMPKα and unc-51-like autophagy activating kinase 1 and Beclin1 protein expression were higher in the IL-15 TG group than in the WT group. IL-15 gene deficiency induces a decrease in autophagy induction. In contrast, IL-15 overexpression could improve muscle quality by activating autophagy induction while decreasing muscle mass. The regulation of IL-15 in autophagy in skeletal muscles may lead to the development of therapies for the autophagy-induced regulation of skeletal muscle mass and cellular quality control.NEW & NOTEWORTHY IL-15 gene deficiency can decrease autophagy induction. However, although IL-15 overexpression induced a decrease in muscle mass, it led to an improvement in muscle quality. Based on these results, understanding the role of IL-15 in regulating autophagy pathways within skeletal muscle may lead to the development of therapies for the autophagy-induced regulation of skeletal muscle mass and cellular quality control.


Assuntos
Interleucina-15 , Músculo Esquelético , Camundongos , Masculino , Animais , Interleucina-15/genética , Interleucina-15/metabolismo , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Camundongos Transgênicos , Camundongos Knockout , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia
3.
Anesthesiology ; 141(1): 56-74, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625708

RESUMO

BACKGROUND: Stimulation of the paraventricular thalamus has been found to enhance anesthesia recovery; however, the underlying molecular mechanism by which general anesthetics modulate paraventricular thalamus is unclear. This study aimed to test the hypothesis that the sodium leak channel (NALCN) maintains neuronal activity in the paraventricular thalamus to resist anesthetic effects of sevoflurane in mice. METHODS: Chemogenetic and optogenetic manipulations, in vivo multiple-channel recordings, and electroencephalogram recordings were used to investigate the role of paraventricular thalamus neuronal activity in sevoflurane anesthesia. Virus-mediated knockdown and/or overexpression was applied to determine how NALCN influenced excitability of paraventricular thalamus glutamatergic neurons under sevoflurane. Viral tracers and local field potentials were used to explore the downstream pathway. RESULTS: Single neuronal spikes in the paraventricular thalamus were suppressed by sevoflurane anesthesia and recovered during emergence. Optogenetic activation of paraventricular thalamus glutamatergic neurons shortened the emergence period from sevoflurane anesthesia, while chemogenetic inhibition had the opposite effect. Knockdown of the NALCN in the paraventricular thalamus delayed the emergence from sevoflurane anesthesia (recovery time: from 24 ± 14 to 64 ± 19 s, P < 0.001; concentration for recovery of the righting reflex: from 1.13% ± 0.10% to 0.97% ± 0.13%, P < 0.01). As expected, the overexpression of the NALCN in the paraventricular thalamus produced the opposite effects. At the circuit level, knockdown of the NALCN in the paraventricular thalamus decreased the neuronal activity of the nucleus accumbens, as indicated by the local field potential and decreased single neuronal spikes in the nucleus accumbens. Additionally, the effects of NALCN knockdown in the paraventricular thalamus on sevoflurane actions were reversed by optical stimulation of the nucleus accumbens. CONCLUSIONS: Activity of the NALCN maintains the excitability of paraventricular thalamus glutamatergic neurons to resist the anesthetic effects of sevoflurane in mice.


Assuntos
Anestésicos Inalatórios , Núcleos da Linha Média do Tálamo , Neurônios , Sevoflurano , Animais , Sevoflurano/farmacologia , Camundongos , Anestésicos Inalatórios/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Núcleos da Linha Média do Tálamo/efeitos dos fármacos , Núcleos da Linha Média do Tálamo/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/fisiologia , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Canais Iônicos , Proteínas de Membrana
4.
J Am Chem Soc ; 145(16): 9242-9253, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37058355

RESUMO

The low salt adsorption capacities (SACs) of benchmark carbon materials (usually below 20 mg g-1) are one of the most challenging issues limiting further commercial development of capacitive deionization (CDI), an energetically favorable method for sustainable water desalination. Sodium superionic conductor (NASICON)-structured NaTi2(PO4)3 (NTP) materials, especially used in combination with carbon to prepare NTP/C materials, provide emerging options for higher CDI performance but face the problems of poor cycling stability and dissolution of active materials. In this study, we report the development of the yolk-shell nanoarchitecture of NASICON-structured NTP/C materials (denoted as ys-NTP@C) using a metal-organic framework@covalent organic polymer (MOF@COP) as a sacrificial template and space-confined nanoreactor. As expected, ys-NTP@C exhibits good CDI performance, including exemplary SACs with a maximum SAC of 124.72 mg g-1 at 1.8 V in the constant-voltage mode and 202.76 mg g-1 at 100 mA g-1 in the constant-current mode, and good cycling stability without obvious performance degradation or energy consumption increase over 100 cycles. Furthermore, X-ray diffraction used to study CDI cycling clearly exhibits the good structural stability of ys-NTP@C during repeated ion intercalation/deintercalation processes, and the finite element simulation shows why yolk-shell nanostructures exhibit better performance than other materials. This study provides a new synthetic paradigm for preparing yolk-shell structured materials from MOF@COP and highlights the potential use of yolk-shell nanoarchitectures for electrochemical desalination.

5.
J Clin Biochem Nutr ; 72(3): 248-255, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37251965

RESUMO

Diabetes mellitus is recognized as a risk factor for sarcopenia. Luseogliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, reduces inflammation and oxidative stress by improving hyperglycemia, subsequently improving hepatosteatosis or kidney dysfunction. However, the effects of SGLT2 inhibitor on the regulation of skeletal muscle mass or function in hyperglycemia are still unknown. In this study, we investigated the effects of luseogliflozin-mediated attenuation of hyperglycemia on the prevention of muscle atrophy. Twenty-four male Sprague-Dawley rats were randomly divided into four groups: control, control with SGLT2 inhibitor treatment, hyperglycemia, and hyperglycemia with SGLT2 inhibitor treatment. The hyperglycemic rodent model was established using a single injection of streptozotocin, a compound with preferential toxicity toward pancreatic beta cells. Muscle atrophy in streptozotocin-induced hyperglycemic model rats was inhibited by the suppression of hyperglycemia using luseogliflozin, which consequently suppressed hyperglycemia-mediated increase in the levels of advanced glycation end products (AGEs) and activated the protein degradation pathway in muscle cells. Treatment with luseogliflozin can restore the hyperglycemia-induced loss in the muscle mass to some degree partly through the inhibition of AGEs-induced or homeostatic disruption of mitochondria-induced activation of muscle degradation.

6.
Angew Chem Int Ed Engl ; 62(9): e202217869, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36625674

RESUMO

Non-aqueous Li-air batteries, despite their high energy density and low cost, have not been deployed practically due to their instability in ambient air, where moisture causes parasitic reactions and shortens their life drastically. Here, we demonstrate the rational design of nanoporous covalent organic frameworks (COFs) as effective gas diffusion layers (GDLs) to address this constraint. The COF GDLs, with a tailor-made pore size of ≈1.4 nm and superhydrophobicity, can limit the intrusion of organic electrolytes and moisture into the gas diffusion channels, enabling high capacity, fast kinetics, and excellent stability of the Li-air batteries. Moreover, we achieve multi-atmosphere Li-air batteries, which can stably cycle under open ambient air (relative humidity up to 95 %) and even in various atmospheres with looping oxygen, humid air, and carbon dioxide. The design principles of our COF GDLs can be universally applied in energy storage and electrochemical systems using organic electrolytes.

7.
Exp Physiol ; 107(3): 222-232, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35100657

RESUMO

NEW FINDINGS: What is the central question of this study? How are the dynamics of interleukin (IL)-15 and its receptors altered during the differentiation of myoblasts into myotubes, and how is IL-15 regulated? What is the main finding and its importance? The mRNA levels of IL-15 and interleukin-2 receptor subunits beta and gamma increase during skeletal muscle differentiation, whereas interleukin-15 receptor subunit alpha (IL-15RA) exhibits different kinetics. IL-15RA regulates the localization and expression of IL-15 at the protein level. ABSTRACT: Interleukin-15 (IL-15) is a myokine in the interleukin-2 (IL-2) family that is generated in the skeletal muscle during exercise. The functional effect of IL-15 involves muscle regeneration and metabolic regulation in skeletal muscle. Reports have indicated that interleukin-15 receptor subunit alpha (IL-15RA) acts by regulating IL-15 localization in immune cells. However, the dynamics of IL-15 and its receptors, which regulate the IL-15 pathway in skeletal muscle differentiation, have not yet been clarified. In this study, we investigated the mechanism of IL-15 regulation using a mouse skeletal muscle cell line, C2C12 cells. We found that the mRNA expression of IL-15, interleukin-2 receptor subunit beta (IL-2RB; CD122) and interleukin-2 receptor subunit gamma (IL-2RG; CD132) increased, but that IL-15RA exhibited different kinetics as differentiation progressed. We also found that IL-15, mainly present in the cytosol, pre-assembled with IL-15RA in the cytosol and fused to the plasma membrane. Moreover, IL-15RA increased IL-15 protein levels. Our findings suggest that genes involved in the IL-15 signalling complex are enhanced with the differentiation of myotubes and that IL-15RA regulates the protein kinetics of IL-15 signalling in skeletal muscle.


Assuntos
Subunidade alfa de Receptor de Interleucina-15 , Interleucina-15 , Interleucina-15/genética , Subunidade alfa de Receptor de Interleucina-15/genética , Subunidade alfa de Receptor de Interleucina-15/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/fisiologia , Mioblastos/metabolismo
8.
Int J Mol Sci ; 23(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36430558

RESUMO

In this study, Irisensata Thunb grass (ITG) was used as a biomass carbon resource to prepare biochars for the first time. After microbial treatment, the obtained microbial-treated ITG (MITG) was activated by using a mixed base as an activator for preparation of biochar (MITGB). The specific surface area and total pore volume of MITGB were 3036.4 m2/g and 1.5252 cm3/g, which were higher than those of biochar prepared without microbial treatment (ITGB, 2930.0 m2/g and 1.5062 cm3/g). Besides, the physicochemical properties of MITGB and ITGB were also quite different including micro morphology, surface chemistry, functional groups, etc. In the experiment of removing organic pollutants with synthetic dye RhB and antibiotic TH as the models, MITGB showed excellent treatment ability. The maximum adsorption capacities of MITGB for RhB and TH were 1354.2 and 1462.6 mg/g, which were higher than most of the biochars. In addition, after five cycles of recycling, the adsorption capacities of the organic pollutant models can still be maintained at more than 80%, which showed high stability. This work verified the feasibility of microbial treatment to further improve the performance of biochar and provided a new idea and direction for exploring other biochars.


Assuntos
Poluentes Ambientais , Porosidade , Carvão Vegetal/química , Adsorção
9.
FASEB J ; 34(11): 14389-14406, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32892438

RESUMO

We hypothesized that pre-exercise may effectively prevent cancer cachexia-induced muscle atrophy in both fast- and slow-twitch muscle types. Additionally, the fast-twitch muscle may be more affected by cancer cachexia than slow-twitch muscle. This study aimed to evaluate the effects of pre-exercise on cancer cachexia-induced atrophy and on atrophy in fast- and slow-twitch muscles. Twelve male Wistar rats were randomly divided into sedentary and exercise groups, and another 24 rats were randomly divided into control, pre-exercise, cancer cachexia induced by intraperitoneal injections of ascites hepatoma AH130 cells, and pre-exercise plus cancer cachexia groups. We analyzed changes in muscle mass and in gene and protein expression levels of major regulators and indicators of muscle protein degradation and synthesis pathways, angiogenic factors, and mitochondrial function in both the plantaris and soleus muscles. Pre-exercise inhibited muscle mass loss, rescued protein synthesis, prevented capillary regression, and suppressed hypoxia in the plantaris and soleus muscles. Pre-exercise inhibited mitochondrial dysfunction differently in fast- and slow-twitch muscles. These results suggested that pre-exercise has the potential to inhibit cancer-cachexia-induced muscle atrophy in both fast- and slow-twitch muscles. Furthermore, the different progressions of cancer-cachexia-induced muscle atrophy in fast- and slow-twitch muscles are related to differences in mitochondrial function.


Assuntos
Caquexia/prevenção & controle , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal/métodos , Animais , Caquexia/etiologia , Linhagem Celular Tumoral , Masculino , Mitocôndrias Musculares/metabolismo , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Atrofia Muscular/etiologia , Neoplasias Experimentais/complicações , Neovascularização Fisiológica , Biossíntese de Proteínas , Ratos , Ratos Wistar
10.
Angew Chem Int Ed Engl ; 60(21): 11943-11948, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33689220

RESUMO

Water-in-salt electrolytes (WISE) have largely widened the electrochemical stability window (ESW) of aqueous electrolytes by formation of passivating solid electrolyte interphase (SEI) on anode and also absorption of the hydrophobic anion-rich double layer on cathode. However, the cathodic limiting potential of WISE is still too high for most high-capacity anodes in aqueous sodium-ion batteries (ASIBs), and the cost of WISE is also too high for practical application. Herein, a low-cost 19 m (m: mol kg-1 ) bi-salts WISE with a wide ESW of 2.8 V was designed, where the low-cost 17 m NaClO4 extends the anodic limiting potential to 4.4 V, while the fluorine-containing salt (2 m NaOTF) extends the cathodic limiting potential to 1.6 V by forming the NaF-Na2 O-NaOH SEI on anode. The 19 m NaClO4 -NaOTF-H2 O electrolyte enables a 1.75 V Na3 V2 (PO4 )3 ∥Na3 V2 (PO4 )3 full cell to deliver an appreciable energy density of 70 Wh kg-1 at 1 C with a capacity retention of 87.5 % after 100 cycles.

11.
FASEB J ; 33(7): 7852-7862, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30916585

RESUMO

We hypothesized that low-intensity endurance exercise might be more effective in preventing cancer cachexia-induced muscle atrophy through both an increase in protein synthesis and a decrease in protein degradation. The purpose of present study was to evaluate the effects and to clarify the mechanism of low-intensity endurance exercise on cancer cachexia-induced muscle atrophy. Twenty-four male Wistar rats were randomly divided into 4 groups: control (Cont), Cont plus exercise (Ex), AH130-induced cancer cachexia (AH130), and AH130 plus Ex. Cancer cachexia was induced by intraperitoneal injections with AH130 Yoshida ascites hepatoma cells; we analyzed the changes in muscle mass and the gene and protein expression levels of major regulators or indicators of skeletal muscle protein degradation and synthesis pathway in the soleus muscles. Low-intensity exercise inhibited the muscle mass loss through a suppression of the ubiquitin-proteasome pathway, increased hypoxia-inducible factor- 1α and phosphorylated AMPK, and inhibited the deactivation of mammalian target of rapamycin pathway in the soleus muscle, which contributed to the prevention of cancer cachexia-induced muscle atrophy. These results suggest that low-intensity exercise has the potential to become an effective therapeutic intervention for the prevention of cancer cachexia-induced muscle atrophy.-Tanaka, M., Sugimoto, K., Fujimoto, T., Xie, K., Takahashi, T., Akasaka, H., Kurinami, H., Yasunobe, Y., Matsumoto, T., Fujino, H., Rakugi, H. Preventive effects of low-intensity exercise on cancer cachexia-induced muscle atrophy.


Assuntos
Caquexia/complicações , Neoplasias Hepáticas Experimentais/complicações , Músculo Esquelético/patologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal , Adenilato Quinase/metabolismo , Animais , Composição Corporal , Hipóxia Celular , Linhagem Celular Tumoral , Força da Mão , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Inflamação , Neoplasias Hepáticas Experimentais/patologia , Masculino , Músculo Esquelético/irrigação sanguínea , Atrofia Muscular/etiologia , Proteínas de Neoplasias/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Distribuição Aleatória , Ratos , Ratos Wistar , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/sangue , Ubiquitina/metabolismo , Ubiquitinação , Redução de Peso
12.
Biochem Biophys Res Commun ; 509(4): 994-1000, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30654941

RESUMO

Skeletal muscle performs 80% of the glucose metabolism in the body. Improvement of insulin resistance and prevention of diabetes by habitual exercise is considered beneficial due to the improved glucose uptake in skeletal muscles. Investigation of the mechanism by which skeletal muscles regulate glucose uptake can contribute to the prevention and treatment of diabetes. Myokines are a kind of cytokine secreted from skeletal muscle, which are expected to regulate muscle metabolism. Interleukin-15 (IL-15) is one such myokine that has been reported to improve glucose metabolism in vitro, although the mechanism remains unclear. In this study, we examined the glucose metabolism of skeletal muscle-specific IL-15 transgenic mice (IL-15TG), and investigated how IL-15 affects glucose metabolism in skeletal muscles. Although High Fat Diet-fed IL-15TG did not exhibit obvious difference in intraperitoneal insulin tolerance test, they had less impaired glucose tolerance compared to wild-type C57BL/6. Phosphorylation of AMP-activated protein kinase (AMPK), Akt substrate of 160 kDa (AS160), tre-2/USP6, BUB2, and cdc16 domain family member 1 (TBC1D1), and translocation of Glucose transporter type 4 (GLUT4) were accelerated in the skeletal muscle of IL-15TG. Our study demonstrated that overexpression of IL-15 in skeletal muscle improves glucose metabolism in skeletal muscle via AMPK pathway. We report the first in-vivo study that describes the signaling pathway of IL-15 in muscle glucose metabolism, and thereby contributes to the elucidation of the regulatory mechanism of muscle glucose metabolism by myokines.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Intolerância à Glucose/tratamento farmacológico , Transportador de Glucose Tipo 4/metabolismo , Interleucina-15/metabolismo , Músculo Esquelético/metabolismo , Animais , Transporte Biológico , Glucose/metabolismo , Glucose/farmacocinética , Resistência à Insulina , Interleucina-15/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Transdução de Sinais
13.
Nano Lett ; 18(3): 2067-2073, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29494167

RESUMO

Because of its ultrahigh specific capacity, lithium metal holds great promise for revolutionizing current rechargeable battery technologies. Nevertheless, the unavoidable formation of dendritic Li, as well as the resulting safety hazards and poor cycling stability, have significantly hindered its practical applications. A mainstream strategy to solve this problem is introducing porous media, such as solid electrolytes, modified separators, or artificial protection layers, to block Li dendrite penetration. However, the scientific foundation of this strategy has not yet been elucidated. Herein, using experiments and simulation we analyze the role of the porous media in suppressing dendritic Li growth and probe the underlying fundamental mechanisms. It is found that the tortuous pores of the porous media, which drastically reduce the local flux of Li+ moving toward the anode and effectively extend the physical path of dendrite growth, are the key to achieving the nondendritic Li growth. On the basis of the theoretical exploration, we synthesize a novel porous silicon nitride submicron-wire membrane and incorporate it in both half-cell and full-cell configurations. The operation time of the battery cells is significantly extended without a short circuit. The findings lay the foundation to use a porous medium for achieving nondendritic Li growth in Li metal-based batteries.

14.
Angew Chem Int Ed Engl ; 58(50): 18246-18251, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31589355

RESUMO

Inducing uniform deposition of lithium from the stage of metal crystallization nucleation is of vital importance to achieve dendrite-free lithium anodes. Herein, using experiments and simulation, homogenization of Li nucleation and normalization of Li growth can be achieved on PNIPAM polymer brushes with lithiophilic functional groups modified Cu substrates. The lithiophilic functional groups of amide O can homogenize ion mass transfer and induce the uniform distribution of Li nucleation sites. What is more, the ultra-small space between each brush can act as the channels for Li transportation and normalization growth. Owing to the synergistic effect of homogenization and normalization of electrodeposited Li, the obtained planar columnar Li anode exhibits excellent cycle stability at an ultra-high current density of 20 mA cm-2 .

15.
J Nanosci Nanotechnol ; 18(12): 8337-8344, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189957

RESUMO

The relatively small electron diffusion coefficient and high charge recombination rate of TiO2 nanoparticle (NP) film limit charge collection in TiO2 NP based dye-sensitized solar cells (DSSCs). Herein, ultralong bending TiO2 (B) nanowires (NWs) were introduced to TiO2 NP photoanode and expected to modify electron transport of DSSCs. The TiO2 (B) NWs/TiO2 NP composite structure was prepared by a facial process combining the stirring hydrothermal method with mechanical mixing method. When the composite structure was applied to DSSCs, the rapid electron transport pathway was formed in photoanode, which was clarified by the small electron transport resistance and long electron diffusion length, improving the charge collection efficiency. Moreover, the scattering effect of TiO2 (B) NWs could enhance the light harvesting, and thus improve the power conversion efficiency (PCE) of DSSCs. The excellent electronic and optical characteristics of TiO2 (B) NWs yield the maximum enhancement of PCE (36.4%) when 50% (wt.%) TiO2 (B) NWs was integrated into TiO2 NP based DSSC. The work provides new insights into the design and tailoring nanowires to enhance the PCE of DSSCs for practical applications.

16.
Small ; 13(42)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28941005

RESUMO

Potassium has its unique advantages over lithium or sodium as a charge carrier in rechargeable batteries. However, progresses in K-ion battery (KIB) chemistry have so far been hindered by lacking suitable electrode materials to host the relatively large K+ ions compared to its Li+ and Na+ counterparts. Herein, molybdenum disulfide (MoS2 ) "roses" grown on reduced graphene oxide sheets (MoS2 @rGO) are synthesized via a two-step solvothermal route. The as-synthesized MoS2 @rGO composite, with expanded interlayer spacing of MoS2 , chemically bonded between MoS2 and rGO, and a unique nano-architecture, displays the one of the best electrochemical performances to date as an anode material for nonaqueous KIBs. More importantly, a combined K+ storage mechanism of intercalation and conversion reaction is also revealed. The findings presented indicate the enormous potential of layered metal dichalcogenides as advanced electrode materials for high-performance KIBs and also provide new insights and understanding of K+ storage mechanism.

17.
Nanotechnology ; 25(45): 455401, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25338125

RESUMO

A novel TiO2 three-dimensional (3D) anode with an aligned TiO2 nanotube/nanoparticle heterostructure (TiO2 NTs/NPs) is developed by simply immersing as-anodized TiO2 NTs into water and further crystallizing the TiO2 NTs by post-annealing. The heterostructure, with its core in a tubular morphology and with both the outer and inner surface consisting of nanoparticles, is confirmed by FESEM and TEM. A reversible areal capacity of 0.126 mAh · cm(-2) is retained after 50 cycles for the TiO2 NTs/NPs heterostructure electrode, which is higher than that of the TiO2 NTs electrode (0.102 mAh · cm(-2) after 50 cycles). At the current densities of 0.02, 0.04, 0.06, 0.08, 0.10 and 0.20 mA · cm(-2), the areal capacities are 0.142, 0.127, 0.117, 0.110, 0.104 and 0.089 mAh · cm(-2), respectively, for the TiO2 NTs/NPs heterostructure electrode compared to the areal capacities of 0.123, 0.112, 0.105, 0.101, 0.094 and 0.083 mAh · cm(-2), respectively, for the the TiO2 NTs electrode. The enhanced electrochemical performance is attributed to the unique microstructure of the TiO2 NTs/NPs heterostructure electrode with the TiO2 NT core used as a straight pathway for electronic transport and with TiO2 NP offering enhanced surface areas for facile Li+ insertion/extraction. The results described here inspire a facile approach to fabricate a 3D anode with an enhanced electrochemical performance for lithium-ion microbattery applications.


Assuntos
Lítio/química , Nanopartículas/química , Nanotubos/química , Níquel/química , Titânio/química , Fontes de Energia Elétrica , Eletroquímica , Íons/química , Tamanho da Partícula , Propriedades de Superfície
18.
Front Neuroanat ; 17: 1162049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37405309

RESUMO

The somatosensory neurons in the dorsal root ganglion (DRG) are responsible to detect peripheral physical and noxious stimuli, and then transmit these inputs into the central nervous system. DRG neurons are composed of various subpopulations, which are suggested to respond to different stimuli, such as mechanical, thermal, and cold perception. For a long time, DRG neurons were classified based on anatomical criteria. Recently, single-cell (scRNA-seq) and single-nucleus RNA-sequencing (snRNA-seq) has advanced our understanding of the composition and functional heterogeneity of both human and rodent DRG neurons at single-cell resolution. In this review, we summarized the current literature regarding single-cell transcriptomic profiling of DRG to provide an integral understanding in the molecular transcriptomes, cell types, and functional annotations of DRG neurons in humans and rodents.

19.
Innovation (Camb) ; 4(4): 100468, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37427353

RESUMO

The radiation tolerance of energy storage batteries is a crucial index for universe exploration or nuclear rescue work, but there is no thorough investigation of Li metal batteries. Here, we systematically explore the energy storage behavior of Li metal batteries under gamma rays. Degradation of the performance of Li metal batteries under gamma radiation is linked to the active materials of the cathode, electrolyte, binder, and electrode interface. Specifically, gamma radiation triggers cation mixing in the cathode active material, which results in poor polarization and capacity. Ionization of solvent molecules in the electrolyte promotes decomposition of LiPF6 along with its decomposition, and molecule chain breaking and cross-linking weaken the bonding ability of the binder, causing electrode cracking and reduced active material utilization. Additionally, deterioration of the electrode interface accelerates degradation of the Li metal anode and increases cell polarization, hastening the demise of Li metal batteries even more. This work provides significant theoretical and technical evidence for development of Li batteries in radiation environments.

20.
ACS Nano ; 17(3): 2901-2911, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36638084

RESUMO

To realize the practical application of lithium-sulfur (Li-S) batteries, there is a need to inhibit uncontrolled Li deposition by facilitating Li-ion migration, and suppress the irreversible consumption of cathodes by preventing polysulfide shuttling. However, a permselective artifical membrane or interlayer which features fast ion transport but low polysulfide crossover is elusive. Here, we report the design and synthesis of a fluorinated covalent organic framework (4F-COF)-based membrane with a high permselectivity and increased battery lifespan. Combining density functional theory calculation, molecular dynamic simulation, and in situ Raman analysis, we demonstrate that fluorinated COF eliminates polysulfides shutting and dendritic lithium formation. Consequently, Li symmetrical cells demonstrate Li plating/stripping behaviors for 2000 h under 1 mA cm-2. More importantly, Li-S batteries based on the 4F-COF/PP separator achieve cycling retention of 82.3% over 1000 cycles at 2 C, rate performance of 568.0 mA h g-1 at 10 C, and an areal capacity of 7.60 mA h cm-2 with a high sulfur loading (∼9 mg cm-2). This work demonstrates that functionalizing nanochannels in COFs can impart permselectivity for energy storage applications.

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