ARCHITECTURE OF FLOWER-LIKE rGO/CNTs-LOADED CuxO NANOPARTICLES AND ITS PHOTOCATALYTIC PROPERTIES

Novel flower-like composite architecture was successfully synthesized by spray drying and post-calcinating method for the first time. Scanning electron microscopy and transmission electron microscopy observations confirmed that reduced graphene oxides/carbon nanotubes hybrid (rGO/CNTs) formed a flower-like micrometer structure and Cu2O , CuO ( Cu x O , x = 1 or 2) nanoparticles were decorated inside them. The photocatalytic properties were further investigated by evaluating the photodegradation of a pollutant methyl orange (MO). The experimental results indicated that this novel architecture enhanced photocatalytic performance with 96.2% decomposition of MO after 25 min in the presence of H 2 O 2 under visible light irradiation, which was much higher than that of Cu x O powders (33.2%). This could be attributed to the more efficient adsorption of MO molecules on flower-like rGO/CNTs and provide a high concentration of MO near to the Cu x O nanoparticles, thus promoting the photocatalytic degradation process.

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Structure of corystospermaceous ovules from the Upper Triassic of Zimbabwe

Botany ◽

10.1139/b09-047 ◽

2009 ◽

Vol 87 (9) ◽

pp. 854-863 ◽

Cited By ~ 4

Author(s):

Georges Barale ◽

Gaëtan Guignard ◽

Marion K. Bamford

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Light Microscopy ◽

Pollen Grains ◽

Upper Triassic ◽

Transmission Electron ◽

Time Scanning ◽

First Time ◽

Scanning Electron

Isolated ovules from the Upper Triassic of Zimbabwe were observed using three complementary approaches: light microscopy and, for the first time, scanning electron microscopy and transmission electron microscopy. Complete ovules showed a curved bifid micropylar tube. Three envelopes were present: integument, nucellus, and megaspore. The integument appeared resiniferous. The nucellus was made up of bulging cells around the pollen chamber, which contained bisaccate pollen grains. The ultrastructure of the nucellus revealed a lamellar organization in their microsinuosities. The megaspore membrane was made up of agglomerate rounded bodies more or less closely arranged and surrounded by two layers. The material may be attributed to Umkomasiaceae. A comparison with ovules of different related groups (seed ferns, Caytoniales, Ginkgoales, Nilssoniales, and Coniferales) was made. The Umkomasiales are considered to be a more primitive group than the Pteridospermales with regard to integument and nucellus.

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Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽

10.3390/min11060611 ◽

2021 ◽

Vol 11 (6) ◽

pp. 611

Author(s):

Celia Marcos ◽

María de Uribe-Zorita ◽

Pedro Álvarez-Lloret ◽

Alaa Adawy ◽

Patricia Fernández ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallite Size ◽

Archaeological Sites ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Infrared And Raman Spectroscopy ◽

First Time ◽

Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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Direct TEM observation of the “acanthite α-Ag2S–argentite β-Ag2S” phase transition in a silver sulfide nanoparticle

Nanoscale Advances ◽

10.1039/c8na00347e ◽

2019 ◽

Vol 1 (4) ◽

pp. 1581-1588 ◽

Cited By ~ 6

Author(s):

S. I. Sadovnikov ◽

E. Yu. Gerasimov

Keyword(s):

Electron Microscopy ◽

Phase Transition ◽

Transmission Electron Microscopy ◽

Silver Sulfide ◽

Transmission Electron ◽

Silver Sulfide Nanoparticles ◽

Microscopy Method ◽

Electron Microscopy Method ◽

First Time

For the first time, the α-Ag2S (acanthite)–β-Ag2S (argentite) phase transition in a single silver sulfide nanoparticles has been observed in situ using a high-resolution transmission electron microscopy method in real time.

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TRANSMISSION ELECTRON MICROSCOPY OF SURFACE AND INTERFACIAL STEPS

Surface Review and Letters ◽

10.1142/s0218625x97000547 ◽

1997 ◽

Vol 04 (03) ◽

pp. 559-566 ◽

Cited By ~ 1

Author(s):

J. M. GIBSON ◽

X. CHEN ◽

O. POHLAND

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Free Surface ◽

Significant Loss ◽

Stress Fields ◽

Preliminary Results ◽

Surface Steps ◽

Transmission Electron ◽

First Time

Transmission electron microscopy is uniquely able to extend techniques for imaging free surface steps to the buried interface regime, without significant loss of detail. Two mechanisms for imaging surface and interfacial steps by transmission electron microscopy are described. They are thickness contrast and strain contrast. The former reveals the position and approximate height of steps, whereas the latter detects stress fields which are commonly associated with steps. The basis for each of these methods is elaborated, and preliminary results are shown for step images at Si/SiO2 interfaces, where measurable stress fields have been directly detected for the first time.

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One-step synthesis of OH-TiO 2 /TiOF 2 nanohybrids and their enhanced solar light photocatalytic performance

Royal Society Open Science ◽

10.1098/rsos.172005 ◽

2018 ◽

Vol 5 (6) ◽

pp. 172005 ◽

Cited By ~ 6

Author(s):

Chentao Hou ◽

Wenli Liu

Keyword(s):

Electron Microscopy ◽

Photocatalytic Performance ◽

Performance Enhancement ◽

Hydrothermal Process ◽

Emission Spectra ◽

Solar Light ◽

Dominant Factor ◽

Simulated Solar Light ◽

Transmission Electron ◽

Naoh Treatment

TiO 2 /TiOF 2 nanohybrids were quickly synthesized through a hydrothermal process using titanium n-butoxide (TBOT), ethanol (C 2 H 5 OH) and hydrofluoric acid as precursors. The prepared nanohybrids underwent additional NaOH treatment (OH-TiO 2 /TiOF 2 ) to enhance their photocatalytic performance. In this paper, the mechanism of NaOH affecting the pathway of transformation from TBOT (Ti precursor) to TiO 2 nanosheets was discussed. The synthesized TiO 2 /TiOF 2 and OH-TiO 2 /TiOF 2 were characterized by field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction pattern (XRD), Fourier infrared spectroscopic analysis (FT-IR), Photoluminescence (PL) emission spectra and UV–visible diffuse reflection spectra (UV–vis DRS). The photocatalytic activity and stability of synthesized samples were evaluated by degradation of methylene blue (MB) under the simulated solar light. The results showed that a larger ratio of TiO 2 to TiOF 2 in TiO 2 /TiOF 2 and OH-TiO 2 /TiOF 2 nanohybrids could allow for even higher MB conversion compared with only TiO 2 nanosheets. NaOH treatment can wash off the F ions from TiOF 2 and induce this larger ratio. The highest efficiency of MB removal was just above 90% in 1 h. Lower electron–hole pairs recombination rate is the dominant factor that induces the photocatalytic performance enhancement of TiO 2 /TiOF 2 nanohybrids. The synthesized OH-TiO 2 /TiOF 2 nanohybrids exhibit great potential in the abatement of organic pollutants.

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Silicon-Sapphire Interface: A High Resolution Electron Microscopy Study

MRS Proceedings ◽

10.1557/proc-2-285 ◽

1980 ◽

Vol 2 ◽

Cited By ~ 1

Author(s):

Fernando A. Ponce

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Silicon Layer ◽

High Resolution Electron Microscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Resolution Limit ◽

High Concentration ◽

Transmission Electron ◽

Resolution Electron

ABSTRACTThe structure of the silicon-sapphire interface of CVD silicon on a (1102) sapphire substrate has been studied in crøss section by high resolution transmission electron microscopy. Multibeam images of the interface region have been obtained where both the silicon and sapphire lattices are directly resolved. The interface is observed to be planar and abrupt to the instrument resolution limit of 3 Å. No interfacial phase is evident. Defects are inhomogeneously distributed at the interface: relatively defect-free regions are observed in the silicon layer in addition to regions with high concentration of defects.

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Magnetic PbFe12O19-TiO2 nanocomposites and their photocatalytic performance in the removal of toxic pollutants

Main Group Metal Chemistry ◽

10.1515/mgmc-2017-0055 ◽

2018 ◽

Vol 41 (3-4) ◽

pp. 53-62 ◽

Cited By ~ 2

Author(s):

Behnaz Lahijani ◽

Kambiz Hedayati ◽

Mojtaba Goodarzi

Keyword(s):

Electron Microscopy ◽

Photocatalytic Performance ◽

Sol Gel ◽

Precipitation Method ◽

X Ray Diffraction ◽

Gel Method ◽

Sol Gel Method ◽

Photocatalytic Effect ◽

Transmission Electron ◽

Ultraviolet Light Irradiation

Abstract In this work, the PbFe12O19 nanoparticles were prepared by the simple and optimized precipitation method with different organic surfactants and capping agents. In the next step, the TiO2 nanoparticles were synthesized using the sol-gel method. At the final step, the PbFe12O19-TiO2 nanocomposites were prepared via the sol-gel method. The effect of the precipitating agent on the morphology and particle size of the products was investigated. The prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The results obtained by the vibrating sample magnetometer show the magnetic properties of the ferrite nanostructures. The photocatalytic effect of the PbFe12O19-TiO2 nanocomposite on the elimination of the azo dyes (acid black, acid violet and acid blue) under ultraviolet light irradiation was evaluated. The results indicate that the prepared nanocomposites have acceptable magnetic and photocatalytic performance.

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Effect of 2,4-Diacetylphloroglucinol on Pythium: Cellular Responses and Variation in Sensitivity Among Propagules and Species

Phytopathology ◽

10.1094/phyto.2003.93.8.966 ◽

2003 ◽

Vol 93 (8) ◽

pp. 966-975 ◽

Cited By ~ 105

Author(s):

Jorge T. de Souza ◽

Christine Arnould ◽

Chrystel Deulvot ◽

Philippe Lemanceau ◽

Vivienne Gianinazzi-Pearson ◽

...

Keyword(s):

Electron Microscopy ◽

Plant Pathogens ◽

Pythium Ultimum ◽

Cellular Responses ◽

Low Ph ◽

Cell Content ◽

Pseudomonas Spp ◽

Transmission Electron ◽

First Time ◽

Resistant Structure

The antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) plays an important role in the suppression of plant pathogens by several strains of Pseudomonas spp. Based on the results of this study, there is variation within and among Pythium spp. to 2,4-DAPG. Also, various propagules of Pythium ultimum var. sporangiiferum, that are part of the asexual stage of the life cycle, differ considerably in their sensitivity to 2,4-DAPG. Mycelium was the most resistant structure, followed by zoosporangia, zoospore cysts, and zoospores. Additionally, we report for the first time that pH has a significant effect on the activity of 2,4-DAPG, with a higher activity at low pH. Furthermore, the level of acetylation of phloroglucinols is also a major determinant of their activity. Transmission electron microscopy studies revealed that 2,4-DAPG causes different stages of disorganization in hyphal tips of Pythium ultimum var. sporangiiferum, including alteration (proliferation, retraction, and disruption) of the plasma membrane, vacuolization, and cell content disintegration. The implications of these results for the efficacy and consistency of biological control of plant-pathogenic Pythium spp. by 2,4-DAPG-producing Pseudomonas spp. are discussed.

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Boron Nitride Nanotubes: Nanoparticles Functionalization and Junction Fabrication

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.120 ◽

2007 ◽

Vol 7 (2) ◽

pp. 530-534 ◽

Cited By ~ 16

Author(s):

Chunyi Zhi ◽

Yoshio Bando ◽

Guozhen Shen ◽

Chengchun Tang ◽

Dmitri Golberg

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Boron Nitride ◽

Boron Nitride Nanotubes ◽

X Ray Diffraction ◽

Carbon Nanostructure ◽

Wet Chemistry ◽

X Ray ◽

Transmission Electron ◽

First Time

Adopting a wet chemistry method, Au and Fe3O4 nanoparticles were functionalized on boron nitride nanotubes (BNNTs) successfully for the first time. X-ray diffraction pattern and transmission electron microscopy were used to characterize the resultant products. Subsequently, a method was proposed to fabricate heterojunction structures based on the particle-functionalized BNNTs. As a demonstration, BNNT-carbon nanostructure, BNNT-ZnO and BNNT-Ga2O3 junctions were successfully fabricated using the functionalized particles as catalysts.

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Ionic Liquids-Containing Silica Microcapsules: A Potential Tunable Platform for Shaping-Up Epoxy-Based Composite Materials?

Nanomaterials ◽

10.3390/nano10050881 ◽

2020 ◽

Vol 10 (5) ◽

pp. 881

Author(s):

Ting Shi ◽

Sébastien Livi ◽

Jannick Duchet ◽

Jean-François Gérard

Keyword(s):

Electron Microscopy ◽

Sol Gel ◽

Diameter Distribution ◽

Excellent Thermal Stability ◽

Transmission Electron ◽

Micron Size ◽

Phosphonium Ionic Liquid ◽

One Step ◽

The One ◽

First Time

In this work, silica microcapsules containing phosphonium ionic liquid (IL), denoted SiO2@IL, were successfully synthesized for the first time using the one step sol-gel method in IL/H20 emulsion. The morphologies of the obtained micron-size microcapsules, including their diameter distribution, were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The thermal behavior of these microcapsules and the mass fraction of the encapsulated IL in the silica microcapsules were determined using thermogravimetric analysis, showing an excellent thermal stability (up to 220 °C) and highlighting that an amount of 20 wt.% of IL is contained in the silica microcapsules. In a second step, SiO2@IL microcapsules (1 wt.%) were dispersed into epoxy-amine networks to provide proof of concept of the ability of such microcapsules to act as healing agents as microcracks propagate into the epoxy networks.

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