[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

There is about 700,000 tonnes of dyes, of more than 10,000 types, that are used as coloring agents in industries, mainly for textile. The release of dyes in natural media is of concern due to their high persistence, toxicity and potential to the bioaccumulate in living organisms. In particular, the most commercialized and carcinogenic azo dyes, that pocess a benzidine function, needs urgent attention. Here, we review the current status of cationic and anionic dyes. We present dye removal techniques using nanoparticles through adsorption and degradation. Among dye removal techniques, adsorption was found the most efficient and cheap. For that, conventional adsorbents such as commercial activated carbon, chitosan and natural waste are often employed. We discuss the use of ZnO, TiO2 and Fe0 to remove dye pollution.

Degradation of hazardous organic dyes in water by nanomaterials

This paper presents an efficient, environmentally friendly, and simple approach for the green synthesis of ZnO nanoparticles (ZnO NPs) using orange fruit peel extract This approach aims to both minimize the use of toxic chemicals in nanoparticle fabrication and enhance the antibacterial activity and biomedical applications of ZnO nanoparticles In this work, an aqueous extract of orange peel was used as the biological reduction agent for the synthesis of ZnO NPs from zinc acetate dihydrate It was found that the size and morphology of the ZnO NPs significantly depended on physicochemical parameters such as the annealing temperature and pH during NP synthesis The ZnO NPs exhibited strong antibacterial activity toward Escherichia coli (E coli) and Staphylococcus aureus (S aureus) without UV illumination at an NP concentration of 0025 mg mL−1 after 8 h of incubation In particular, the bactericidal activity towards S aureus varied extensively with the synthesis parameters This study presents an efficient green synthesis route for ZnO NPs with a wide range of potential applications, especially in the biomedical field

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Green synthesis of ZnO nanoparticles using orange fruit peel extract for antibacterial activities

Biosynthesis of zinc oxide nanoparticles (ZnO-NPs) was achieved by utilizing the reducing and capping potential of leaf, stem and callus aqueous extracts of Mussaenda frondosa.The bioreduced ZnO-NPs were characterized using powder X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis spectroscopy), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS) techniques. UV–visible spectra of ZnO-NPs showed a strong absorption peak at 370, 376 and 373 nm corresponding to the band gap energy of 3.33, 3.27 and 3.30 eV for ZnO-NPs obtained from leaf (L-ZnO-NP), stem (S-ZnO-NP) and callus (C-ZnO-NP) aqueous extracts, respectively. XRD analysis confirmed the formation of hexagonal wurtzite structures having an average grain size between 5 and 20 nm in diameter. FTIR spectra revealed the presence of stretching vibrations of –O–H, C–H, C–N, C = O groups involved in reduction and stabilization of nanoparticles. SEM images recognize the presence of spongy, spherical, porous agglomerated nanoparticles. DLS analysis and zeta potential values validated the stability of ZnO-NPs. The present investigation puts light on the photocatalytic activity and biological (antioxidant, anti-inflammatory, antidiabetic, antimicrobial, anticancerous) applications of ZnO-NPs. The current study is an attempt to describe an effective, simple and eco-friendly method of ZnO-NP synthesis and to evaluate its potential for various industrial and medical applications.

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Green synthesis of zinc oxide nanoparticles from the leaf, stem and in vitro grown callus of Mussaenda frondosa L.: characterization and their applications

Semiconductor-based heteronanostructures with the high carriers-flow steering and high activity and stability in the visible-light-driven multicomponent photocatalytic system have been of great concern due to its long-standing demand in the wide application of environmental protection and energy conversion. However, the construction of ternary-component nanocrystals usally undergos multiple complex steps to restrict its application. In the work, we successfully report the facile design and synthesis of a novel double Z-scheme Zn3(VO4)2/Zn2V2O7/ZnO ternary heteronanostructure system (THS) via self-phase transition with heating on basis of the Zn3(OH)2V2O7·2H2O precursor in a low-cost microwave hydrothermal assistant, which exhibited excellent photocatalytic performances. In this case, the employment of Zn3(OH)2V2O7·2H2O as the heteronanostructure precursor is the key for fabricating the THS material, which not only boosted the interaction with its structure and but also maintained the mesoporous nanosheet structure. It has been proved that Zn3(OH)2V2O7·2H2O firstly lost it H2O and then the partial Zn3(VO4)2 underwent the self-phase transition process to produce Zn2V2O7 and ZnO (Zn3(OH)2V2O7·2H2O → Zn3(VO4)2 → Zn2V2O7 + ZnO), which obtained the double Z-scheme THS. Accordingly, the interfacial-dominated photocatalysis reactivities such as the removal of phenols and dyes were used as ideal experiments to verify the responsibility of the constructed double Z-scheme THS material that was equipped with the narrow band gap, intimate contact interface, the wide visible light absortion and more efficient charge transfer and separation for high visible-light photocatalytic reactivity and stable cycling. PL spectra, radicals trapping experiments and ESR tests confirmed that the nontraditional transport of photoinduced h+ and e− caused by double Z-scheme mechanism played an important role in the efficient removing the target pollutants. Such a synthetic approach maybe render double Z-scheme THS to advance the development for large-scale applications of the hetero-transition metal vanadates.

Phase transformation and microwave hydrothermal guided a novel double Z-scheme ternary vanadate heterojunction with highly efficient photocatalytic performance

Eco-friendly and green synthesis of BiVO4 nanoparticle using microwave irradiation as photocatalayst for the degradation of Alizarin Red S

In this paper, a green synthesis of ZnO nanoparticles using Phyllanthus embilica stem extract as a reducing/capping agent. The prepared ZnO nanoparticles were characterized using fourier transform infrared spectroscopy (FTIR), UV-visible diffuse reflectance spectroscopy (UV-vis-DRS), X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The synthesized ZnO nanoparticles are wurtzite hexagonal structure with an average average crystallite size of ZnO prepared using Phyllanthus embilica stem extract was smaller (25.96 nm) when compared to the same ZnO prepared using a chemical method (36.73 nm). FT-IR spectra revealed the functional groups and the presence of protein as the stabilizing agent for surrounding the ZnO nanoparticles. The antibacterial activity of the ZnO was tested against gram negative bacteria Salmonella typhi and Klebsiella phnemonea by disc diffusion method. ZnO nanoparticles were subjected to antimicrobial studies and significant results were obtained.

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Green synthesis of ZnO Nanoparticles using Phyllanthus embilica Stem extract and their Antibacterial activity

Enhancing the visible light induced photocatalytic properties of WO3 nanoparticles by doping with vanadium

A new Schiff base derived from cuminaldehyde and 4-aminoantipyrine and its metal complexes with Co(II), Ni(II), Cu(II) and Zn(II) have been synthesized and characterized. Their structural features have been established on the basis of analytical, magnetic, conductance, IR, UV- visible, mass, 1 H NMR spectral studies. The low conductance values indicate that the complexes are non-electrolytes. On the basis of colour, magnetic moments and electronic spectral data, octahedral geometry was assigned to Co(II) and Ni((II) complexes, while Cu(II) complex showed distorted octahedral arrangement. The antimicrobial activity of the ligand and its complexes has been studied with Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Proteus vulgaris, Candida albicans and Aspergillus niger, employing agar-well diffusion method. Both the Schiff base as well as its complexes possess significant antimicrobial activity.

Synthesis, Spectral Characterization and Antimicrobial Studies of Schiff base Transition Metal Complexes derived from Cuminaldehyde and 4-Aminoantipyrine

Crystal structure, chemical nuclease activity, and VHPO mimicking potential of oxovanadium(IV) complexes—A combined experimental and computational study

C. Joel

Papers

Eco-friendly and green synthesis of BiVO4 nanoparticle using microwave irradiation as photocatalayst for the degradation of Alizarin Red S

Green synthesis of ZnO Nanoparticles using Phyllanthus embilica Stem extract and their Antibacterial activity

Enhancing the visible light induced photocatalytic properties of WO3 nanoparticles by doping with vanadium

Synthesis, Spectral Characterization and Antimicrobial Studies of Schiff base Transition Metal Complexes derived from Cuminaldehyde and 4-Aminoantipyrine

Crystal structure, chemical nuclease activity, and VHPO mimicking potential of oxovanadium(IV) complexes—A combined experimental and computational study