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1.
Small ; : e2403702, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39087377

RESUMO

This research addresses challenges with silver nanowires (Ag NWs) as transparent conductive electrodes (TCEs) and heaters in commercial devices. Here, zinc oxide nanoparticles (ZnO NPs) are first reported as a protective layer for Ag NWs. Multi-physics simulations confirm enhanced thermal stability due to improved heat dissipation, temperature distribution, and thermal conductivity from ZnO. When Ag NWs are surrounded by air, heat transfers mainly through convection and radiation because of air's low conduction coefficient. Encasing Ag NWs in ZnO enhances heat transfer to the ZnO surface, accelerating cooling and dissipating more heat into the atmosphere via convection. The results show composite's efficiency in the Joule effect, maintaining a consistent temperature of 78 °C for 700 s after 500 bending cycles, a significant improvement over Ag NWs operating for only 5 s at 80 °C. Additionally, the composite film exhibited exceptional performance, including a sheet resistance of 9.8 Ω sq-1 and an optical transmittance of 96.96 %, outperforming Ag NWs, which have a sheet resistance of 12 Ω sq-1 and a transmittance of 94.11%. The combination of enhanced electrical, thermal, and mechanical stability, along with impressive optical properties, makes Ag NWs/ZnO NPs a promising candidate for transparent conductive electrode materials in various applications.

2.
Bioresour Technol ; 298: 122386, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31740245

RESUMO

Dwindling petroleum resources and increasing environmental concerns have stimulated the production of platform chemicals via biochemical processes through the use of renewable carbon sources. Various types of biomass wastes, which are biodegradable and vastly underutilized, are generated worldwide in huge quantities. They contain diverse chemical constituents, which may serve as starting points for the manufacture of a wide range of valuable bio-derived platform chemicals, intermediates, or end products via different conversion pathways. The valorization of inexpensive, abundantly available, and renewable biomass waste could provide significant benefits in response to increasing fossil fuel demands and manufacturing costs, as well as emerging environmental concerns. This review explores the potential for the use of available biomass waste to produce important chemicals, such as monosaccharides, oligosaccharides, biofuels, bioactive molecules, nanocellulose, and lignin, with a focus on commercially viable technologies.


Assuntos
Biocombustíveis , Lignina , Biomassa , Carbono
3.
Bioresour Technol ; 244(Pt 1): 1039-1048, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28851158

RESUMO

A novel, integrated process for economical high-yield production of d-mannose and ethanol from coffee residue waste (CRW), which is abundant and widely available, was reported. The process involves pretreatment, enzymatic hydrolysis, fermentation, color removal, and pervaporation, which can be performed using environmentally friendly technologies. The CRW was pretreated with ethanol at high temperature and then hydrolyzed with enzymes produced in-house to yield sugars. Key points of the process are: manipulations of the fermentation step that allowing bioethanol-producing yeasts to use almost glucose and galactose to produce ethanol, while retaining large amounts of d-mannose in the fermented broth; removal of colored compounds and other components from the fermented broth; and separation of ethanol and d-mannose through pervaporation. Under optimized conditions, approximately 15.7g dry weight (DW) of d-mannose (approximately 46% of the mannose) and approximately 11.3g DW of ethanol from 150g DW of ethanol-pretreated CRW, were recovered.


Assuntos
Biocombustíveis , Café , Manose , Saccharomyces cerevisiae , Etanol , Fermentação , Hidrólise
4.
Bioresour Technol ; 161: 280-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24713602

RESUMO

An integrated detoxification process with electrodialysis (ED) followed by adsorption was performed to remove fermentation inhibitors from hemicellulose hydrolysates. The hydrolysates were prepared by oxalic acid pretreatment of yellow poplars at different temperatures. Of fermentation inhibitors, acetic acid showed high removal efficiency of about 90% and high transport rate during the ED process without membrane fouling. The integration of the detoxification processes increased up to the ethanol yield of 0.33g/g sugar, the ethanol production of about 9g/L, and the productivity of 0.12g/Lh, while the fermentation of non-detoxified hydrolysates did not produce bioethanol. The influence of inhibitor concentration on the fermentability showed that HMF had the highest inhibition effect. The results clearly showed that an integrated detoxification process with ED followed by adsorption removed fermentation inhibitors with high efficiency and increased the fermentability of the oxalic acid pretreated hemicellulose hydrolysates.


Assuntos
Biocombustíveis , Técnicas Eletroquímicas , Liriodendron/química , Polissacarídeos/química , Adsorção , Fermentação , Hidrólise , Ácido Oxálico , Madeira/química
5.
Bioresour Technol ; 152: 444-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24321607

RESUMO

A two-step detoxification process consisting of electrodialysis and adsorption was performed to improve the fermentability of oxalic acid hydrolysates. The constituents of the hydrolysate differed significantly between mixed hardwood and softwood. Acetic acid and furfural concentrations were high in the mixed hardwood, whereas 5-hydroxymethylfurfural (HMF) concentration was relatively low compared with that of the mixed softwood. The removal efficiency of acetic acid reached 100% by electrodialysis (ED) process in both hydrolysates, while those of furfural and HMF showed very low, due to non-ionizable properties. Most of the remaining inhibitors were removed by XAD-4 resin. In the mixed hardwood hydrolysate without removal of the inhibitors, ethanol fermentation was not completed. Meanwhile, both ED-treated hydrolysates successfully produced ethanol with 0.08 and 0.15 g/Lh ethanol productivity, respectively. The maximum ethanol productivity was attained after fermentation with 0.27 and 0.35 g/Lh of detoxified hydrolysates, which were treated by ED, followed by XAD-4 resin.


Assuntos
Diálise/métodos , Eletroquímica/métodos , Fermentação , Ácido Oxálico/metabolismo , Adsorção , Biomassa , Cromatografia Líquida , Condutividade Elétrica , Etanol/metabolismo , Hidrólise , Inativação Metabólica , Lignina/metabolismo , Espectrometria de Massas
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