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1.
Small ; 20(7): e2306258, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37806759

RESUMEN

Aqueous alkaline Zn-based batteries (AAZBs) possess great promise for large-scale applications thanks to their higher discharging plateau and unique reaction mechanism. However, the capacity and rate capability of Ni-based cathodes are still unsatisfactory due to their insufficient OH- adsorption and diffusion ability. Herein, heterostructured Ni3 S2 /Ni(OH)2 nanosheets with outstanding electrochemical performance are synthesized via a facile chemical etching strategy. The heterostructured Ni3 S2 /Ni(OH)2 nanosheet cathode shows significantly increased capacity and rate capability due to its boosted OH- adsorption and diffusion ability compared to Ni3 S2 . Consequently, the assembled Zn//Ni3 S2 /Ni(OH)2 cell can deliver an ultrahigh capacity of 2.26 mAh cm-2 , an excellent rate performance (0.91 mAh cm-2 at 100 mA cm-2 ) and a satisfying cycling stability (1.01 mAh cm-2 at 20 mA cm-2 after 500 cycles). Moreover, a prominent energy density of 3.86 mWh cm-2 is obtained, which exceeds the majority of recently reported AAZBs. This work is expected to provide a new modification direction for developing high-performance nickel sulfide cathode for AAZBs.

2.
Ying Yong Sheng Tai Xue Bao ; 33(7): 1861-1870, 2022 Jul.
Artículo en Chino | MEDLINE | ID: mdl-36052789

RESUMEN

Exploring and quantifying the impacts of biological soil crusts on soil hydrological processes and soil water budget in semi-arid ecosystems can provide a theoretical basis for vegetation restoration and reconstruction in deserts. Based on continuous observation of soil water content in different types of areas covered by biological soil crusts (e.g., algae, moss) and bare sand in the Mu Us sandy land during the growing season (May to October) from 2018 to 2020, we examined the effects of biological soil crusts on soil water budget at a depth of 0-40 cm. Results showed that algae and moss crusts significantly reduced soil water supplement below 40 cm by rainfall and increased soil water evaporation loss, compared with that under bare sand. In the relatively wet year (2018), the amount of soil water expenditure (seepage+evaporation) covered by bare sand and the various types of biological soil crusts was less than that of rainfall, resulting in net soil water income. In the relative dry years (2019 and 2020), the amount of soil water expenditure covered by dominant algae and moss crusts was higher than that of rainfall, causing net soil water deficit, but opposite for bare sand. Biological soil crusts led to the imbalance of soil water budget of 0-40 cm depth and even soil water deficit in relatively dry years, which may lead to the succession of plant communities to be dominated by shallow-rooted plants in this area.


Asunto(s)
Briófitas , Suelo , China , Clima Desértico , Ecosistema , Plantas , Arena , Microbiología del Suelo , Agua/análisis
3.
Chem Commun (Camb) ; 57(56): 6931-6934, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34156043

RESUMEN

The exploration of high-performance cathode candidates is of great significance for aqueous aluminum-metal batteries (AAMBs). Here, we, for the first time, report tetrachloro-1,4-benzoquinone (TCQ) as a superior organic AAMB cathode. Owing to its high reversible conversion between the carbonyl and hydroxyl groups, the TCQ cathode delivers a remarkable electrochemical performance.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 252: 119526, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33582438

RESUMEN

In this work, a dual-functional Cu2+-based ensemble (2S·Cu2+) was well designed and characterized. Then, the successional and discriminating sensing for CN- over other competitive species (H2PO4- and biothiols) was achieved based on the disaggregation of 2S·Cu2+ ensemble and the deprotonation of imidazole NH of regenerated sensor S in aqueous solution, respectively. The visual sensing mechanism could be clearly demonstrated by 1H NMR, HRMS and energy changes between the HOMO-LUMO band gaps. Furthermore, the reversibility and reusability of S and 2S·Cu2+ upon alternating addition of CN-/H+ and CN-/Cu2+ were studied. Interestingly, the sequential sensing for biothiols (cysteine, glutathione and homocysteine) and CN- was also realized through spectroscopic methodology and test paper strips. This work may provide a feasible strategy to discriminate CN- over H2PO4- and biothiols with high selectivity and sensitivity through Cu2+-based ensembles.

5.
Adv Sci (Weinh) ; 7(21): 2002173, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33173741

RESUMEN

Zinc (Zn) holds great promise as a desirable anode material for next-generation rechargeable batteries. However, the uncontrollable dendrite growth and low coulombic efficiency of the Zn plating/stripping process severely impede further practical applications of Zn-based batteries. Here, these roadblocks are removed by using in situ grown zeolitic imidazolate framework-8 (ZIF-8) as the ion modulation layer to tune the diffusion behavior of Zn2+ ions on Zn anodes. The well-ordered nanochannels and N species of ZIF-8 can effectively homogenize Zn2+ flux distribution and modulate the plating/stripping rate, ensuring uniform Zn deposition without dendrite growth. The Zn corrosion and hydrogen evolution are also alleviated by the insulating nature of ZIF-8, resulting in high coulombic efficiency. Therefore, the Zn@ZIF anode shows highly reversible, dendrite-free Zn plating/stripping behavior under a broad range of current densities, and a symmetric cell using this anode can work correctly up to 1200 h with a low polarization at 2 mA cm-2. Moreover, this ultrastable Zn@ZIF anode also enables a full Zn ion battery with outstanding cyclic stability (10 000 cycles).

6.
ChemSusChem ; 13(6): 1568-1574, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-31736252

RESUMEN

Hydrated vanadium pentoxide (VO) cathodes with two-dimensional bilayer structures hold great potential for advanced aqueous Zn-ion batteries (ZIBs) construction, but their further application is impeded by the poor cycling stability. Herein, to address this issue and enhance the Zn ion storage capability, La3+ with a big radius was selected to finely tune their nanostructure. The strategic introduction of La3+ to VO led to the formation of LaVO4 , which showed larger interplanar spacing, better electrical conductivity, and superior Zn-ion diffusion efficiency. These unique characteristics were beneficial in the (de)intercalation and the prevention of electrode degradation/collapse, thereby significantly strengthening the corresponding electrochemical performance. As a consequence, the cathode possessed a high specific capacity of 472.5 mAh g-1 at a current density of 0.38 A g-1 and displayed good rate performance, accompanied by enduring cycling stability (no decay after 2000 cycles). Besides, when equipped as an aqueous ZIB, it delivered an outstanding peak energy density of 341.9 Wh kg-1 and a peak power density of 3.22 kW kg-1 , surpassing most VO-based energy-storage devices.

7.
Hepatol Res ; 46(13): 1392-1401, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26969900

RESUMEN

AIM: The translationally controlled tumor protein (TCTP) has been reported to promote progression of many physiological processes. However, whether TCTP is involved in liver regeneration has been rarely studied. This study aimed to investigate the potential role of serum TCTP in liver regeneration after two-thirds partial hepatectomy. METHODS: The synthesis rate and accumulated expression of TCTP was assessed by phosphor imaging and Western blot analysis, respectively. The mRNA expression of tctp was analyzed by quantitative real-time PCR. The effect of serum TCTP on hepatocyte proliferation was investigated by bromodeoxyuridine incorporation, liver/body weight ratio, albumin concentration, and histological examination of liver following treatment of rat with anti-TCTP antibody or prokaryotic TCTP protein before hepatectomy. The MTT assay was used to examine effect of TCTP on hepatocyte proliferation in vitro. RESULTS: The results showed that the expression of intracellular and serum TCTP protein was significantly increased in rats after two-thirds partial hepatectomy. In vivo bromodeoxyuridine labeling assay suggested that treatment with anti-TCTP antibody before hepatectomy significantly decreased hepatocyte proliferation and liver/body weight ratio. The prokaryotic TCTP had a potential promoting effect on hepatocyte proliferation both in vivo and in vitro, although prokaryotic TCTP given to rats prior to hepatectomy did not increase the proliferation ratio or liver/body weight ratio. Furthermore, anti-TCTP antibody pretreatment decreased the expression of cyclin E, cdk2, and interleukin-6 in rat liver. CONCLUSION: These findings suggest serum TCTP is involved in rat liver regeneration through promoting hepatocyte proliferation.

8.
Opt Lett ; 40(23): 5455-8, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26625024

RESUMEN

Embedding a thin metal layer between two thin dielectric or semiconductor layers [dielectric/metal/dielectric (DMD)] leads to a kind of transparent electrode that is promising as a substitute for the currently widely applied indium tin oxide electrode. However, the optical and electrical properties of DMD still wait for further improvement. In this study, Ar plasma irradiation (API) was, for the first time to our knowledge, applied to improve the optical and electrical properties of a TiO2/Ag/TiO2 electrode that was fabricated by electron-beam evaporation of TiO2 and electric-resistance heating of high purity Ag under vacuum. Ar plasma was produced by radio frequency glow discharge. The Ag layer was bombarded before the second layer of TiO2 was deposited. The electrode with configuration of TiO2 (24 nm)/Ag(14 nm)/TiO2 (24 nm) after API for 10 s shows excellent performance. The mean transmittance between 370 and 800 nm reaches 94% and the sheet resistance is as low as 6 Ω/sq, while Haacke's figure of merit is as high as 112×10(-3) Ω(-1). The improvement mechanism is discussed based on field emission scanning electron microscope images and absorption spectra. The improvement is attributed to the fact that API reduces the localized surface plasmon resonance of Ag nanoparticles and makes the Ag film thinner and denser.

9.
Exp Dermatol ; 24(12): 947-52, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26186482

RESUMEN

MicroRNAs (miRNA) are key players in a variety of cancers including malignant melanoma. miR-137 has been reported to be a tumor suppressor in melanoma and several targets have been identified for this miRNA. We previously developed a novel proteomics technology, (35) S in vivo/vitro labelling analysis for dynamic proteomics (SiLAD). Because of its high sensitivity in analysing protein expression rates, SiLAD has the potential to unravel miRNA effects on mRNAs coding for proteins with long half-lives or high abundance. Using SiLAD, we discovered that miR-137 significantly downregulated the expression rate of p21-activated kinase 2 (PAK2) in melanoma cells. Bioinformatics analysis predicted PAK2 as a direct target of miR-137, which was confirmed by luciferase reporter assay and Western blot analysis. We found that overexpression of miR-137 inhibited the proliferation of melanoma cells, which could be phenocopied by knockdown of PAK2 using siRNAs. Furthermore, overexpression of PAK2 restored miR-137-mediated suppression of cell proliferation. These findings indicate that miR-137 could inhibit proliferation through targeting PAK2 in melanoma cells.


Asunto(s)
Melanoma/genética , Melanoma/patología , MicroARNs/genética , Quinasas p21 Activadas/antagonistas & inhibidores , Quinasas p21 Activadas/genética , Apoptosis/genética , Apoptosis/fisiología , Línea Celular Tumoral , Proliferación Celular/genética , Proliferación Celular/fisiología , Regulación hacia Abajo , Técnicas de Silenciamiento del Gen , Humanos , Melanoma/metabolismo , MicroARNs/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , ARN Interferente Pequeño/genética , Transfección , Quinasas p21 Activadas/metabolismo
10.
Electrophoresis ; 36(14): 1622-32, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25873423

RESUMEN

Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, (35) S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through (35) S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5-5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration.


Asunto(s)
Regeneración Hepática , Hígado/fisiología , Biosíntesis de Proteínas , Proteínas/metabolismo , Proteómica , Animales , Hepatectomía , Hígado/cirugía , Masculino , Mapas de Interacción de Proteínas , Proteínas/análisis , Ratas , Ratas Sprague-Dawley
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