Large-scale and green synthesis of octahedral flower-like cupric oxide nanocrystals with enhanced photochemical properties

2014 ◽  
Vol 315 ◽  
pp. 169-177 ◽  
Author(s):  
Shi-Kuo Li ◽  
Yu-Yi Pan ◽  
Mi Wu ◽  
Fang-Zhi Huang ◽  
Chuan-Hao Li ◽  
...  
Keyword(s):  
Green Synthesis ◽  
Large Scale ◽  
Cupric Oxide ◽  
Photochemical Properties

The preparation and photochemical properties of some 1,3-Diphenyl-2-pyrazolines containing a heteroaromatic substituent

1977 ◽  
Vol 30 (3) ◽  
pp. 629 ◽  
Author(s):  
J Lin ◽  
DE Rivett ◽  
JFK Wilshire
Keyword(s):  
Photochemical Reaction ◽  
Large Scale ◽  
Polar Solvent ◽  
Methanolic Solution ◽  
Pyrazoline Ring ◽  
Photochemical Properties

Several 1,3-diphenyl- and 1,3,5-triphenyl-2-pyrazolines containing a heteroaromatic substituent (viz. imidazol-1-yl, pyrazol-1-yl and 1,2,4- triazol-1-yl) have been synthesized. When compared with their unsubstituted analogues, these compounds (a) absorbed more intensely at a longer wavelength, (b) exhibited greater fluorescence in a polar solvent (methanol) and (c) possessed similar stability to light. ��� Large-scale irradiations of two 1,3,5-triphenyl-2-pyrazolines (viz. unsubstituted and that containing the 1,2,4-triazol-1-yl substituent) in methanolic solution revealed that, although dehydrogenation of the 2-pyrazoline ring was the major photochemical reaction, significant oxidation to the corresponding chalcone also occurred. In addition, phenol was detected among the irradiation products. ��� Several sulphonated analogues of the abovementioned pyrazolines were prepared. When applied to wool, these compounds exhibited excellent fluorescent whitening properties.

CHARACTERIZATION, ANTIMICROBIAL, AND METABOLIC ACTIVITY OF GREEN AND CHEMICALLY SYNTHESIZED ZINC OXIDE NANOPARTICLES

2019 ◽  
pp. 11-17
Author(s):  
SUMATHI S ◽  
BANUPRIYA SJS ◽  
AKHILA V ◽  
PADMA PR
Keyword(s):  
Zinc Oxide ◽  
Chemical Synthesis ◽  
Green Synthesis ◽  
Zinc Oxide Nanoparticles ◽  
Large Scale ◽  
Cost Effective ◽  
Oxide Nanoparticles ◽  
Antibiofilm Activity ◽  
Bacterial Strains ◽  
Hemolysis Assay

Objectives: The aim of the present study is a synthesis of zinc oxide nanoparticles (ZnONPs) by green and chemical method. The nanoparticles were tested for their antimicrobial, antibiofilm activity, biocompatibility, and hemolysis activity. Methods: We have synthesized ZnONPs both by green and chemical synthesis using the coprecipitation method. To understand the functional group, absorbance, crystalline nature, size, and shape of the synthesized particles, Fourier transform infrared (FTIR), ultraviolet–visible spectroscopy, X-ray diffraction, and scanning electron microscopy were done. Antibacterial activity was carried out using different bacterial strains. The cytotoxicity of synthesized nanoparticles was checked using MTT assay with Klebsiella pneumoniae. Antibiofilm activities of both synthesized nanoparticles were done using Staphylococcus aureus and to assess the toxicity of nanoparticles at the cellular level, hemolysis assay was performed. Results: The yield of nanoparticles in green synthesis was much higher when compared to chemical synthesis. Spectral results showed that the synthesized nanoparticles were ZnONPs. Antibacterial, antibiofilm, and hemolysis assay showed that green nanoparticles were more potent than chemical nanoparticles. Conclusion: Hence, green synthesis provides an advantage over chemical synthesis as it is cost effective, environmentally friendly, and easily scaled up for large-scale synthesis.

scholarly journals A unique clade of light-driven proton-pumping rhodopsins evolved in the cyanobacterial lineage

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Masumi Hasegawa ◽  
Toshiaki Hosaka ◽  
Keiichi Kojima ◽  
Yosuke Nishimura ◽  
Yu Nakajima ◽  
...  
Keyword(s):  
Large Scale ◽  
Expression System ◽  
Genomic Analysis ◽  
Proton Pumping ◽  
Spectroscopic Characteristics ◽  
Light Utilization ◽  
Photochemical Properties ◽  
Microbial Rhodopsin ◽  
Unique Clade ◽  
Biased Distribution

Abstract Microbial rhodopsin is a photoreceptor protein found in various bacteria and archaea, and it is considered to be a light-utilization device unique to heterotrophs. Recent studies have shown that several cyanobacterial genomes also include genes that encode rhodopsins, indicating that these auxiliary light-utilizing proteins may have evolved within photoautotroph lineages. To explore this possibility, we performed a large-scale genomic survey to clarify the distribution of rhodopsin and its phylogeny. Our surveys revealed a novel rhodopsin clade, cyanorhodopsin (CyR), that is unique to cyanobacteria. Genomic analysis revealed that rhodopsin genes show a habitat-biased distribution in cyanobacterial taxa, and that the CyR clade is composed exclusively of non-marine cyanobacterial strains. Functional analysis using a heterologous expression system revealed that CyRs function as light-driven outward H+ pumps. Examination of the photochemical properties and crystal structure (2.65 Å resolution) of a representative CyR protein, N2098R from Calothrix sp. NIES-2098, revealed that the structure of the protein is very similar to that of other rhodopsins such as bacteriorhodopsin, but that its retinal configuration and spectroscopic characteristics (absorption maximum and photocycle) are distinct from those of bacteriorhodopsin. These results suggest that the CyR clade proteins evolved together with chlorophyll-based photosynthesis systems and may have been optimized for the cyanobacterial environment.

Completely green synthesis of silver nanoparticle decorated MWCNT and its antibacterial and catalytic properties

2016 ◽  
Vol 88 (1-2) ◽  
pp. 71-81 ◽  
Author(s):  
Sneha Mohan ◽  
Oluwatobi S. Oluwafemi ◽  
Sandile P. Songca ◽  
Didier Rouxel ◽  
Patrice Miska ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Green Synthesis ◽  
Silver Nanoparticle ◽  
Large Scale ◽  
Hybrid Nanocomposites ◽  
Antibacterial Efficacy ◽  
Hybrid Nanocomposite ◽  
Ag Nps ◽  
Simple Method ◽  
G Ratio

AbstractWe herein report a simple large scale green synthesis route for the synthesis of silver nanoparticle (Ag-NP) multi walled carbon nanotubes (MWCNTs) hybrid nanocomposite (Ag-MWCNTs). The as-synthesized hybrid nanocomposite were characterized using UV-Vis absorption spectroscopy, Fourier transform infra-red spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction analysis (XRD) and high resolution transmission electron microscopy (HR-TEM). Raman spectroscopy analysis showed an increase in the D/G ratio of Ag-MWCNTs hybrid nanocomposites when compare with that of functionalized MWCNTs (F-MWCNTs) attributed to the presence of Ag-NPs on the surface of the F-MWCNTs. The as-synthesized Ag-MWCNTs nanocomposites showed strong antibacterial efficacy against Escherichia coli compared to the Ag-NPs and MWCNTs. The catalytic potential of the Ag-MWCNTs hybrid nanocomposite was investigated for the first time by studying the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride at 299 K at various reaction times. The reaction follows first order kinetics with a rate constant of 5.18×10−1 s−1. It is believed that, the large scale synthesis of such hybrid nanocomposites via simple method using non-toxic reagent will not only enhance its antibacterial efficacy, durability and biocompatibility, it will also minimize its biotoxcity and environmental impacts.

scholarly journals Copper Oxide Nanomaterials Prepared by Solution Methods, Some Properties, and Potential Applications: A Brief Review

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Thi Ha Tran ◽  
Viet Tuyen Nguyen
Keyword(s):  
Large Scale ◽  
Cupric Oxide ◽  
Bulk Material ◽  
Precursor Solution ◽  
High Quality ◽  
Chemical Methods ◽  
Narrow Bandgap ◽  
Solution Methods ◽  
Potential Applications ◽  
Near Future

Cupric oxide (CuO), having a narrow bandgap of 1.2 eV and a variety of chemophysical properties, is recently attractive in many fields such as energy conversion, optoelectronic devices, and catalyst. Compared with bulk material, the advanced properties of CuO nanostructures have been demonstrated; however, the fact that these materials cannot yet be produced in large scale is an obstacle to realize the potential applications of this material. In this respect, chemical methods seem to be efficient synthesis processes which yield not only large quantities but also high quality and advanced material properties. In this paper, the effect of some general factors on the morphology and properties of CuO nanomaterials prepared by solution methods will be overviewed. In terms of advanced nanostructure synthesis, microwave method in which copper hydroxide nanostructures are produced in the precursor solution and sequentially transformed by microwave into CuO may be considered as a promising method to explore in the near future. This method produces not only large quantities of nanoproducts in a short reaction time of several minutes, but also high quality materials with advanced properties. A brief review on some unique properties and applications of CuO nanostructures will be also presented.

Large Scale, Green Synthesis of a Generation-1 Melamine (Triazine) Dendrimer

2009 ◽  
pp. 151-160 ◽  
Author(s):  
Abdellatif Chouai ◽  
Vincent J. Venditto ◽  
Eric E. Simanek
Keyword(s):  
Green Synthesis ◽  
Large Scale

Large scale synthesis of ultrathin cupric oxide nanosheets via a rapid microwave-assisted and template-free route

2018 ◽  
Vol 214 ◽  
pp. 138-141
Author(s):  
Xingrong Han ◽  
Fan Liao ◽  
Yanfei Zhang ◽  
Chunju Xu ◽  
Huiyu Chen
Keyword(s):  
Large Scale ◽  
Cupric Oxide ◽  
Microwave Assisted ◽  
Template Free ◽  
Large Scale Synthesis

scholarly journals Green Synthesis of Highly Concentrated and Stable Colloidal Dispersion of Core-Shell Silver Nanoparticles (AgNPs-Shell) and their Antimicrobial and Ultra-high Catalytic Properties

2021 ◽  
Author(s):  
Azam Ali ◽  
Mehrukh Zehravi ◽  
Muhammad Humble Khalid Treen ◽  
Jiri Militky ◽  
Fiaz Hussain ◽  
...  
Keyword(s):  
Green Synthesis ◽  
Tannic Acid ◽  
Large Scale ◽  
Catalytic Properties ◽  
Average Particle Size ◽  
Colloidal Dispersion ◽  
Alkaline Condition ◽  
Core Shell ◽  
Average Particle ◽  
One Pot

The versatile one-pot green synthesis of a highly concentrated and stable colloidal dispersion of AgNPs was carried out using the self-assembled tannic acid without using any other hazardous chemicals. Tannic acid (Plant-based polyphenol) was used as a reducing and stabilizing agent for silver nitrate in a mild alkaline condition. The synthesized AgNPs were characterized for their concentration, capping, size distribution, and shape. The experimental results confirmed the successful synthesis of nearly spherical and highly concentrated (2281 ppm) AgNPs, capped with poly-tannic acid (AgNPs-PTA). The average particle size of AgNPs-PTA was found 9.90 ± 1.60 nm. The colloidal dispersion of synthesized nanoparticles was observed stable for more than 15 months in the ambient environment (25 oC, 65 % relative humidity). The synthesized AgNPs-PTA showed an effective antimicrobial activity against Staphylococcus Aureus Escherichia coli. Ag-PTA also exhibited enhanced catalytic properties. It reduces 4-nitrophenol into 4-aminophenol in the presence of NaBH4 with a normalized rate constant (Knor = K/m) of 615.04 mL·s-1·mg-1. Furthermore, AgNPs-PTA were stable for more than 15 months under ambient conditions. The unique core-shell structure and ease of synthesis render the synthesized nanoparticles superior to others, with potential for large-scale applications, especially in the field of catalysis and biomedical.

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