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1.
Small ; 20(24): e2306447, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38152988

RESUMEN

Due to their anisotropy, 1D semiconductor nanorod-based materials have attracted much attention in the process of hydrogen production by solar energy. Nevertheless, the rational design of 1D heterojunction materials and the modulation of photo-generated electron-hole transfer paths remain a challenge. Herein, a ZnxCd1-xS@ZnS/MoS2 core-shell nanorod heterojunction is precisely constructed via in situ growth of discontinuous ZnS shell and MoS2 NCs on the Zn─Cd─S nanorods. Among them, the Zn vacancy in the ZnS shell builds the defect level, and the nanoroelded MoS2 builds the electron transport site. The optimized photocatalyst shows significant photocatalytic activity without Platinum as an auxiliary catalyst, mainly due to the new interfacial charge transfer channel constructed by the shell vacancy level, the vertical separation and the de-accumulation process of photo-generated electrons and photo-generated holes. At the same time, spectral analysis, and density functional theory (DFT) calculations fully prove that shortening difference of speed between the photogenerated electron and hole movement process is another key factor to enhance the photocatalytic performance. This study provides a new path for the kinetic design of enhanced carrier density by shortening the carrier retention time of 1D heterojunction photocatalysts with improved photocatalytic performance.

2.
Chem Commun (Camb) ; (41): 5215-7, 2008 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-18956073

RESUMEN

A novel approach to produce hydrogen from bio-oil was obtained with high carbon conversion (>90%) and hydrogen yield (>90%) at T<500 degrees C by using the electrochemical catalytic reforming of oxygenated-organic compounds over 18%NiO/Al(2)O(3) reforming catalyst; thermal electrons play important promoting roles in the decomposition and reforming of the oxygenated-organic compounds in the bio-oil.


Asunto(s)
Fuentes de Energía Bioeléctrica , Hidrógeno/química , Compuestos Orgánicos/química , Óxido de Aluminio/química , Carbono/química , Catálisis , Electroquímica , Electrones , Oxígeno/química , Espectrometría de Masa por Ionización de Electrospray
3.
Food Chem Toxicol ; 119: 375-379, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29425934

RESUMEN

Phenolic acids and flavonoids in bamboo leaves are of great importance for their functional attributes, but they can hardly be separated simultaneously. In this study, zirconia was prepared and applied as a potential absorbent for simultaneous separation of these phenolic compounds. Three phenolic acids (neochlorogenic acid, chlorogenic acid and cryptochlorogenic acid) and two flavonoids (isoorientin and orientin) were isolated at the same time. The influence of bamboo leaves extraction conditions, zirconia calcination temperatures, desorption conditions and absorption/desorption dynamics on the separation were further investigated. When zirconia-400 (calcined at 400 °C) was treated with 70% ethanol extract of bamboo leaves for 40 min followed by desorption with 70% acetic acid solution for 60 min, the recovery of three chlorogenic acids and two flavonoids was about 65%. To conclude, the concise method developed here may provide a new way for simultaneous separation of phenolic acids and flavonoids from various plants.


Asunto(s)
Bambusa/química , Ácido Clorogénico/química , Ácido Clorogénico/aislamiento & purificación , Flavonoides/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Circonio/química , Cromatografía Líquida de Alta Presión , Hidroxibenzoatos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray
4.
Bioresour Technol ; 102(10): 6239-45, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21392976

RESUMEN

A novel approach for high efficient conversion of the CO(2)-rich bio-syngas into the CO-rich bio-syngas was carried out by using biomass char and Ni/Al(2)O(3) catalyst, which was successfully applied for production of bio-methanol from bio-oil. After the bio-syngas conditioning, the CO(2)/CO ratio prominently dropped from 6.33 to 0.01-0.28. The maximum CO yield in the bio-syngas conditioning process reached about 1.96 mol/(mol CO(2)) with a nearly complete conversion of CO(2) (99.5%). The performance of bio-methanol synthesis was significantly improved via the conditioned bio-syngas, giving a maximum methanol yield of 1.32 kg/(kg(catalyst)h) with a methanol selectivity of 99%. Main reaction paths involved in the bio-syngas conditioning process have been investigated in detail by using different model mixture gases and different carbon sources.


Asunto(s)
Biomasa , Dióxido de Carbono/metabolismo , Metanol/metabolismo
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