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1.
Angew Chem Int Ed Engl ; 58(47): 16764-16769, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31339216

RESUMO

Nicotinamide adenine dinucleotide (NAD+ ) is one of the most well-known redox cofactors carrying electrons. Now, it is reported that the intrinsically charged NAD+ motif can serve as an active electrode in electrochemical lithium cells. By anchoring the NAD+ motif by the anion incorporation, redox activity of the NAD+ is successfully implemented in conventional batteries, exhibiting the average voltage of 2.3 V. The operating voltage and capacity are tunable by altering the anchoring anion species without modifying the redox center itself. This work not only demonstrates the redox capability of NAD+ , but also suggests that anchoring the charged molecules with anion incorporation is a viable new approach to exploit various charged biological cofactors in rechargeable battery systems.


Assuntos
Fontes de Energia Elétrica , Eletroquímica/instrumentação , Eletrodos , Lítio/química , Niacinamida/química , Oxirredução
2.
ArXiv ; 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36748002

RESUMO

We study the boundary continuity of solutions to fully nonlinear elliptic equations. We first define a capacity for operators in non-divergence form and derive several capacitary estimates. Secondly, we formulate the Wiener criterion, which characterizes a regular boundary point via potential theory. Our approach utilizes the asymptotic behavior of homogeneous solutions, together with Harnack inequality and the comparison principle.

3.
Polymers (Basel) ; 14(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35335503

RESUMO

Hydrogen is nowadays considered a favorable and attractive energy carrier fuel to replace other fuels that cause global warming problems. Water electrolysis has attracted the attention of researchers to produce green hydrogen mainly for the accumulation of renewable energy. Hydrogen can be safely used as a bridge to successfully connect the energy demand and supply divisions. An alkaline water electrolysis system owing to its low cost can efficiently use renewable energy sources on large scale. Normally organic/inorganic composite porous separator membranes have been employed as a membrane for alkaline water electrolyzers. However, the separator membranes exhibit high ionic resistance and low gas resistance values, resulting in lower efficiency and raised safety issues as well. Here, in this study, we report that zirconia toughened alumina (ZTA)-based separator membrane exhibits less ohmic resistance 0.15 Ω·cm2 and low hydrogen gas permeability 10.7 × 10-12 mol cm-1 s-1 bar-1 in 30 wt.% KOH solution, which outperforms the commercial, state-of-the-art Zirfon® PERL separator. The cell containing ZTA and advanced catalysts exhibit an excellent performance of 2.1 V at 2000 mA/cm2 at 30 wt.% KOH and 80 °C, which is comparable with PEM electrolysis. These improved results show that AWEs equipped with ZTA separators could be superior in performance to PEM electrolysis.

4.
Anticancer Res ; 42(7): 3445-3452, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35790271

RESUMO

BACKGROUND/AIM: Copine 1 (CPNE1) is a calciumdependent phospholipid protein that has been shown to regulate the AKT serine/threonine kinase 1 (AKT) signaling pathway to mediate its function in various cell types. However, little is known about the physiological function of this protein in breast cancer cells. We aimed to investigate the prognostic and therapeutic value of CPNE1 in erb-b2 receptor tyrosine kinase 2 [human epidermal growth factor receptor 2 (HER2)]-positive and luminal A subtypes of breast cancer. MATERIALS AND METHODS: Western blotting, cell viability, wound-healing and invasion assays were performed on SK-BR3 and MCF-7 breast cancer cells with forced overexpression of CPNE1. CPNE1 immunohistochemical (IHC) staining and bioinformatics analysis were performed on specimens from patients with breast cancer and compared to normal breast samples. RESULTS: CPNE1 overexpression promoted AKT activation, and increased cell viability and cell motility in SK-BR3 and MCF-7 breast cancer cells. In addition, invasive capabilities of SK-BR3 cells were increased by the overexpression of CPNE1. The expression levels of CPNE1 were higher in HER2-positive and luminal A subtypes of human breast cancer tissues compared with those in adjacent normal tissues. Furthermore, CPNE1 expression was increased in RNA microarray analysis of samples from patients with breast cancer compared to normal breast samples. CONCLUSION: CPNE1 may play a key role in the pathophysiology of HER2-positive and luminal A subtypes of breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Humanos , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ativação Transcricional , Regulação para Cima
5.
Front Chem ; 9: 787787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869233

RESUMO

Alkaline water electrolysis (AWE) is a mature water electrolysis technology that can produce green hydrogen most economically. This is mainly attributed to the use of Ni-based materials that are easy to process and inexpensive. The nickel-based meshes with various structures such as woven mesh and expanded mesh are widely used as electrode in the AWE due to its common availability and easy fabrication. However, the morphological effect of meshes on hydrogen evolution reaction (HER) performance has not been studied. Here a new parameter to determine the structural effect of mesh on HER performance was first proposed. The key factors of the parameter were found to be the strand width, pore width and the strand surface area. The woven mesh with the ratio of pore width to strand width that converges to 1 showed the lowest the overpotential. The expanded mesh with the higher the structural surface area exhibited the lowest the overpotential. This study will help to choose an optimal structure for the mesh with the HER electrode.

6.
Adv Mater ; 30(42): e1704682, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29582467

RESUMO

Organic rechargeable batteries, which use organics as electrodes, are excellent candidates for next-generation energy storage systems because they offer design flexibility due to the rich chemistry of organics while being eco-friendly and potentially cost efficient. However, their widespread usage is limited by intrinsic problems such as poor electronic conductivity, easy dissolution into liquid electrolytes, and low volumetric energy density. New types of organic electrode materials with various redox centers or molecular structures have been developed over the past few decades. Moreover, research aimed at enhancing electrochemical properties via chemical tuning has been at the forefront of organic rechargeable batteries research in recent years, leading to significant progress in their performance. Here, an overview of the current developments of organic rechargeable batteries is presented, with a brief history of research in this field. Various strategies for improving organic electrode materials are discussed with respect to tuning intrinsic properties of organics using molecular modification and optimizing their properties at the electrode level. A comprehensive understanding of the progress in organic electrode materials is provided along with the fundamental science governing their performance in rechargeable batteries thus a guide is presented to the optimal design strategies to improve the electrochemical performance for next-generation battery systems.

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