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1.
Nat Commun ; 14(1): 4210, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452034

RESUMO

Hydrogen production coupled with biomass upgrading is vital for future sustainable energy developments. However, most biomass electrooxidation reactions suffer from high working voltage and low current density, which substantially hinder large-scale industrial applications. Herein, we report an acidic hydrogen production system that combined anodic ascorbic acid electrooxidation with cathodic hydrogen evolution. Unlike C-H and O-H bonds cleavage with slow kinetics in conventional organic oxidation, the highly active enol structure in ascorbic acid allows for an ultralow overpotential of only 12 mV@10 mA/cm2 using Fe single-atom catalysts, and reaches 1 A/cm2 at only 0.75 V (versus reversible hydrogen electrode) with approximately 100% Faraday efficiency for hydrogen production. Furthermore, the fabricated two-electrode membrane-free electrolyser delivers an industrial current density of 2 A/cm2@1.1 V at 60 °C (2.63 kWh/Nm3 H2), which requires half of the electricity consumption in conventional water electrolysis (~5 kWh/Nm3 H2). This work provides a new avenue for achieving industrial-scale hydrogen production from biomass.


Assuntos
Ácido Ascórbico , Eletricidade , Biomassa , Eletrodos , Hidrogênio
2.
Research (Wash D C) ; 6: 0040, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040520

RESUMO

Layered materials with unique structures and symmetries have attracted tremendous interest for constructing 2-dimensional (2D) structures. The weak interlayer interaction renders them to be readily isolated into various ultrathin nanosheets with exotic properties and diverse applications. In order to enrich the library of 2D materials, extensive progress has been made in the field of ternary layered materials. Consequently, many brand-new materials are derived, which greatly extend the members of 2D realm. In this review, we emphasize the recent progress made in synthesis and exploration of ternary layered materials. We first classify them in terms of stoichiometric ratio and summarize their difference in interlayer interaction, which is of great importance to produce corresponding 2D materials. The compositional and structural characteristics of resultant 2D ternary materials are then discussed so as to realize desired structures and properties. As a new family of 2D materials, we overview the layer-dependent properties and related applications in the fields of electronics, optoelectronics, and energy storage and conversion. The review finally provides a perspective for this rapidly developing field.

3.
Adv Mater ; 33(33): e2101845, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34250646

RESUMO

One important goal of the current electrocatalysis is to develop integrated electrodes from the atomic level design to multilevel structural engineering in simple ways and low prices. Here, a series of oxygen micro-alloyed high-entropy alloys (O-HEAs) is developed via a metallurgy approach. A (CrFeCoNi)97 O3 bulk O-HEA shows exceptional electrocatalytic performance for the oxygen evolution reaction (OER), reaching an overpotential as low as 196 mV and a Tafel slope of 29 mV dec-1 , and with stability longer than 120 h in 1 m KOH solution at a current density of 10 mA cm-2 . It is shown that the enhanced OER performance can be attributed to the formation of island-like Cr2 O3 microdomains, the leaching of Cr3+ ions, and structural amorphization at the interfaces of the domains. These findings offer a technological-orientated strategy to integrated electrodes.

4.
ACS Appl Mater Interfaces ; 13(6): 7227-7237, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33550809

RESUMO

Finding highly efficient and reusable catalysts for advanced oxidation processes is a crucial endeavor to resolve the severe water pollution problems. Although numerous nanocatalysts have been developed in the past few decades, their recyclability along with sustainably high catalytic efficiency still remain challenging. Here, we propose a new strategy for designing efficient and reusable catalysts, that is, introducing Cu as a reductant into a metallic glass-based catalyst and constructing three-dimensional hierarchical porous architectures via a laser 3D printing technique. The as-printed 3D porous MG/Cu catalysts exhibit exceptional catalytic efficiency in degrading RhB with a normalized rate constant approximately 620 times higher than commercial nano zero-valent iron, outperforming most reported Fenton-type catalysts so far. Strikingly, the catalysts exhibit an excellent reusability and can be used more than 100 times (the highest record so far) without apparent efficiency decay. It is revealed that Cu-doping could improve the surface reducibility and promote the electronic transfer, rendering the 3D-printed MG/Cu catalysts with a sustainably active Fe(II)-rich surface and, therefore, unprecedented reusability. This work offers a broadly applicable design route for the development of advanced catalysts with an outstanding combination of activity and reusability for wastewater treatments.

5.
Nat Prod Res ; 30(10): 1215-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26140441

RESUMO

A new Bacillus amyloliquefaciens named ZJU-2011 was discovered, and the culture supernatant showed a strong inhibitory effect against Candida albicans. In this study, a novel method was developed to purify the antifungal compounds in high purity. The obtained products were analysed by high performance liquid chromatography and proven to be of high purity. Mass spectrometry showed that the molecular weights of the two bioactive components were 270 and 288, respectively, and their structures were determined to be bacilysin and chlorotetaine by using (1)H and (13)C nuclear magnetic resonance spectroscopy. To the best of our knowledge, this is the first time that B. amyloliquefaciens has been reported to produce bacilysin and chlorotetaine simultaneously. The minimum inhibitory concentration of chlorotetaine against six common fungal pathogens were determined to be in the range of 1.8-7.8 µg/mL.


Assuntos
Antifúngicos/isolamento & purificação , Bacillus/química , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Dipeptídeos/isolamento & purificação , Dipeptídeos/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Estrutura Molecular
6.
Curr Top Med Chem ; 16(9): 901-16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26303430

RESUMO

Compared with the increasing and widespread bacterial resistance to clinical medicines and the urgent need for cures of intractable diseases, there is a dramatic decline in the numbers of drugs reaching the market or clinical trials. Accordingly, it has become imperative to discover more rational and efficient strategies to design and develop novel drugs. Structure-based drug design/discovery (SBDD) is one of the computer-aided methods, by which novel drugs are designed or discovered based on the knowledge of 3D structures of the relevant specific targets. During the past few decades, the great potentials and success of SBDD have been seen in the field of drug discovery. In this review, we present an overview of the key mechanisms of SBDD, the frequently used computer programs in SBDD and the reported successful cases. Finally, several typical design processes of lead components from SBDD are also highlighted in detail, such as the discovery of inhibitors of G protein-coupled receptors (GPCRs), antibacterial drugs, and anti-cancer drugs.


Assuntos
Descoberta de Drogas , Desenho de Fármacos , Modelos Moleculares , Estrutura Molecular
7.
Curr Pharm Biotechnol ; 16(1): 11-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25420726

RESUMO

Fragment-based drug discovery (FBDD) has caused a revolution in the process of drug discovery and design, with many FBDD leads being developed into clinical trials or approved in the past few years. Compared with traditional high-throughput screening, it displays obvious advantages such as efficiently covering chemical space, achieving higher hit rates, and so forth. In this review, we focus on the most recent developments of FBDD for improving drug discovery, illustrating the process and the importance of FBDD. In particular, the computational strategies applied in the process of FBDD and molecular-docking programs are highlighted elaborately. In most cases, docking is used for predicting the ligand-receptor interaction modes and hit identification by structurebased virtual screening. The successful cases of typical significance and the hits identified most recently are discussed.


Assuntos
Descoberta de Drogas/métodos , Simulação de Acoplamento Molecular , Humanos
8.
J Zhejiang Univ Sci B ; 14(4): 346-54, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23549852

RESUMO

A 24-membered ring macrolide compound, macrolactin A has potential applications in pharmaceuticals for its anti-infectious and antiviral activity. In this study, macrolactin A was produced by a marine bacterium, which was identified as Bacillus subtilis by 16S ribosomal RNA (rRNA) sequence analysis. Electrospray ionization mass spectrometry (ESI/MS) and nuclear magnetic resonance (NMR) spectroscopy analyses were used to characterize this compound. To improve the production, response surface methodology (RSM) involving Box-Behnken design (BBD) was employed. Faeces bombycis, the main by-product in sericulture, was used as a nitrogen source in fermentation. The interactions between three significant factors, F. bombycis, soluble starch, and (NH4)2SO4 were investigated. A quadratic model was constructed to fit the production and the factors. Optimum medium composition was obtained by analysis of the model. When cultivated in the optimum medium, the production of macrolactin A was increased to 851 mg/L, 2.7 times as compared to the original. This study is also useful to find another way in utilizing F. bombycis.


Assuntos
Bacillus subtilis/metabolismo , Reatores Biológicos/microbiologia , Macrolídeos/isolamento & purificação , Macrolídeos/metabolismo , Modelos Biológicos , Água do Mar/microbiologia , Amido/metabolismo , Bacillus subtilis/classificação , Simulação por Computador , Interpretação Estatística de Dados , Especificidade da Espécie
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