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1.
Photochem Photobiol ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943225

RESUMO

Elevated global pollution level is the prime reason that contributes to the onset of various harmful health diseases. The products of Biginelli reaction are enormously used in the pharmaceutical industry as they have antiviral, antibacterial, and calcium channel modulation abilities. This work reports a novel eosin Y sensitized boron graphitic carbon nitride (EY-Ben-g-C3N4) as a photocatalyst that efficiently produced 3,4-dihydropyrimidine-2-(1H)-one by the Biginelli reaction of benzaldehyde, urea, and methyl acetoacetate. The photocatalyst EY-Ben-g-C3N4 showed a successful generation of 3,4-dihydropyrimidine-2-(1H)-one (Biginelli product) in good yield via photocatalysis which is an eco-friendly method and has facile operational process. In addition to the production of Biginelli products, the photocatalyst also showed a remarkable NADH regeneration of 81.18%. The incorporation of g-C3N4 with boron helps increase the surface area and the incorporation of eosin Y which is an inexpensive and non-toxic dye, and in Ben-g-C3N4, enhanced the light-harvesting capacity of the photocatalyst. The production of 3,4-dihydropyrimidine-2-(1H)-one and NADH by the EY-Ben-g-C3N4 photocatalyst is attributed to the requisite band gap, high molar absorbance, low rate of charge recombination, and increased capacity of the photocatalyst to harvest solar light energy.

2.
Chemosphere ; 353: 141491, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395365

RESUMO

Photocatalysis has emerged as a promising approach for generating solar chemical and organic transformations under the solar light spectrum, employing polymer photocatalysts. In this study, our aim is to achieve the regeneration of NADH and fixation of nitroarene compounds, which hold significant importance in various fields such as pharmaceuticals, biology, and chemistry. The development of an in-situ nature-inspired artificial photosynthetic pathway represents a challenging task, as it involves harnessing solar energy for efficient solar chemical production and organic transformation. In this work, we have successfully synthesized a novel artificial photosynthetic polymer, named TFc photocatalyst, through the Friedel-Crafts alkylation reaction between triptycene (T) and a ferrocene motif (Fc). The TFC photocatalyst is a promising material with excellent optical properties, an appropriate band gap, and the ability to facilitate the regeneration of NADH and the fixation of nitroarene compounds through photocatalysis. These characteristics are necessary for several applications, including organic synthesis and environmental remediation. Our research provides a significant step forward in establishing a reliable pathway for the regeneration and fixation of solar chemicals and organic compounds under the solar light spectrum.


Assuntos
NAD , Energia Solar , Fotossíntese , Luz , Luz Solar , Compostos Orgânicos/química
3.
Photochem Photobiol ; 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38102890

RESUMO

A solvent-free sulfur-bridge-eosin-Y (SBE-Y) polymeric framework photocatalyst was prepared for the first time through an in situ thermal polymerization route using elemental sulfur (S8 ) as a bridge. The addition of a sulfur bridge to the polymeric framework structure resulted in an allowance of the harvesting range of eosin-Y (E-Y) for solar light. This shows that a wider range of solar light can be used by the bridge material's photocatalytic reactions. In this context, supercharged solar spectrum: enhancing light absorption and hole oxidation with sulfur bridges. This suggests that the excited electrons and holes through solar light can contribute to oxidation-reduction reactions more potently. As a result, the photocatalyst-enzyme attached artificial photosynthesis system developed using SBE-Y as a photocatalyst performs exceptionally well, resulting in high 1,4-NADH regeneration (86.81%), followed by its utilization in the exclusive production of formic acid (210.01 µmol) from CO2 and synthesis of fine chemicals with 99.9% conversion yields. The creation of more effective photocatalytic materials for environmental clean-up and other applications that depend on the solar light-driven absorption spectrum of inorganic and organic molecules could be one of the practical ramifications of this research.

4.
Chemosphere ; 341: 139697, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37567274

RESUMO

Indeed, the development of ecologically benign molecular fabrication methods for highly efficient graphene quantum dots-based photocatalysts is of great significant. Graphene quantum dots-based photocatalysts have promising applications in various field, including environmental remediation, energy conversion, and splitting of water. However, ensuring resource reusability and minimizing the environmental impact are crucial considerations in the development. From this perspective, attention has also been paid to the creation of easy to make solar light harvesting graphene quantum dots-based photocatalysts for synthesising pharmaceuticals and functional imines compounds. Imines are excellent significant building blocks in pharmaceutical chemistry and excellent examples of these valuable compounds' synthetic intermediates, and the environmentally friendly oxidative synthesis of imines from amines. Therefore, herein, we designed a facile and efficient condensation route to synthesize the Nen-GQDs@PH photocatalyst. This route involves coupling of 2,4-dinitrophenylhydrazine (PH) with nitrogen-enriched graphene quantum dots (Nen-GQDs). The Nen-GQDs@PH as photocatalyst functions in a highly selective and efficient manner, leading to high amines conversion efficiency to imines (95%). Our results highlight a novel and environmentally safe approach for generating highly selective imines from various types of amines, setting a new benchmark in the current research field.


Assuntos
Grafite , Pontos Quânticos , Grafite/química , Pontos Quânticos/química , Aminas/química , Iminas
5.
Angew Chem Int Ed Engl ; 55(5): 1728-32, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26791882

RESUMO

Active sites in carbon-catalyzed phosgene synthesis from gaseous CO and Cl2 have been identified using C60 fullerene as a model catalyst. The carbon atoms distorted from sp(2) coordination in non-planar carbon units are concluded to generate active Cl2 . Experiments and density functional theory calculations indicate the formation of a surface-bound [C60 ⋅⋅⋅Cl2 ] chlorine species with radical character as key intermediate during phosgene formation. It reacts rapidly with physisorbed CO in a two-step Eley-Rideal-type mechanism.

6.
Zoolog Sci ; 28(1): 25-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21186943

RESUMO

Earthworms are one of the most important and beneficial macrofauna, and are used extensively in organic farming. Earthworms mediate soil biological regulation systems, and produce biogenic structures. They help to maintain soil structure, water infiltration, and regulate the availability of nutrients assimilated by plants. The objectives of this study were to perform morphological and molecular characterizations of 24 earthworm individuals collected from geographically diverse locations to assess the level of genetic variation. For molecular analysis, the effectiveness of RAPD, ISSR, and Universal rice primers (URPs) markers was investigated to identify polymorphism among 24 isolates of earthworms. A total of 62 molecular markers were used for amplification of genomic DNA of earthworms. Of these, 10 RAPD, 10 ISSR, and 10 URPs markers were used for characterization, which showed 95.7%, 96.7% and 98.3% polymorphism, respectively. The dendrogram, generated from the DNA markers by the unweighted pair group method using arithmetic averages, grouped all the isolates into two main clusters. All Eisenia fetida isolates were clustered in group A, whereas group B included three isolates belonging to Eudrilus eugeniae. Molecular markers allowed a rapid assessment of genetic variation among these closely related isolates of earthworms. These results suggest that molecular markers are a good choice for diversity analysis of earthworm individuals.


Assuntos
DNA/genética , Marcadores Genéticos , Variação Genética , Oligoquetos/genética , Animais , Hidrocarbonetos Aromáticos com Pontes , Análise por Conglomerados , Impressões Digitais de DNA , Demografia , Filogenia , Pirazóis
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