scholarly journals Calculator program for the comparison of particle size distribution measurements between transmission electron microscopy and the liquid centrifuge technique

1977 ◽  
Author(s):  
F Postma, Jr
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Transmission Electron

scholarly journals The Domain and Microstructure of Resin-Bonded Magnets

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2849
Author(s):  
Marcin Jan Dośpiał
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Size ◽  
Size Distribution ◽  
Domain Structure ◽  
Grain Size Distribution ◽  
Exchange Interactions ◽  
Force Microscopy ◽  
Transmission Electron ◽  
Scanning Electron

This paper presents domain and structure studies of bonded magnets made from nanocrystalline Nd-(Fe, Co)-B powder. The structure studies were investigated using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Mössbauer spectroscopy and X-ray diffractometry. On the basis of performed qualitative and quantitative phase composition studies, it was found that investigated alloy was mainly composed of Nd2(Fe-Co)14B hard magnetic phase (98 vol%) and a small amount of Nd1.1Fe4B4 paramagnetic phase (2 vol%). The best fit of grain size distribution was achieved for the lognormal function. The mean grain size determined from transmission electron microscopy (TEM) images on the basis of grain size distribution and diffraction pattern using the Bragg equation was about ≈130 nm. HRTEM images showed that over-stoichiometric Nd was mainly distributed on the grain boundaries as a thin amorphous border of 2 nm in width. The domain structure was investigated using a scanning electron microscope and metallographic light microscope, respectively, by Bitter and Kerr methods, and by magnetic force microscopy. Domain structure studies revealed that the observed domain structure had a labyrinth shape, which is typically observed in magnets, where strong exchange interactions between grains are present. The analysis of the domain structure in different states of magnetization revealed the dynamics of the reversal magnetization process.

Synthesis and Characterization of Water-Soluble Monolayer-Protected Gold Nanoparticles

2011 ◽  
Vol 415-417 ◽  
pp. 617-620 ◽  
Author(s):  
Yan Su ◽  
Ying Yun Lin ◽  
Yu Li Fu ◽  
Fan Qian ◽  
Xiu Pei Yang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Gold Nanoparticles ◽  
Average Particle Size ◽  
Water Soluble ◽  
Synthesis And Characterization ◽  
Average Particle ◽  
Transmission Electron

Water-soluble gold nanoparticles (AuNPs) were prepared using 2-mercapto-4-methyl-5- thiazoleacetic acid (MMTA) as a stabilizing agent and sodium borohydride (NaBH4) as a reducing agent. The AuNPs product was analyzed by transmission electron microscopy (TEM), UV-vis absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR). The TEM image shows that the particles were well-dispersed and their average particle size is about 5 nm. The UV-vis absorption and FTIR spectra confirm that the MMTA-AuNPs was stabilized by the carboxylate ions present on the surface of the AuNPs.

Introduction of Nanoscale Porous Aromatic Frameworks in PTMSP Matrix

2020 ◽  
Vol 869 ◽  
pp. 28-39
Author(s):  
Danila Bakhtin ◽  
Leonid Kulikov ◽  
Alexander Malakhov ◽  
Stepan D. Bazhenov
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Ir Spectroscopy ◽  
Suzuki Reaction ◽  
Main Idea ◽  
Polymeric Materials ◽  
Transmission Electron ◽  
Porous Aromatic Framework ◽  
Porous Aromatic Frameworks

Samples of nanoscale nano-PAF-10 and nano-PAF-24 porous aromatic framework-like polymeric materials were synthesized using the Suzuki reaction in a microemulsion. Monomers were tetrakis-(p-bromophenyl)methane and 1,4-phenylenediboronic acid. The main idea of the approach is to use 1,4-phenylenediboronic acid not only as a direct participant in the reaction, but also as a surfactant, which allows to stabilize the drops of the emulsion. Using this procedure, samples of PAF-like polymers were synthesized from the mixture, containing the mixture of tetrakis(p-bromophenyl)methane and 1,4-phenylenediboronic acid in ratio from 1:2 to 1:6; the reaction was conducted from 10 to 24 hours. The resulting materials were characterized by IR spectroscopy, NMR spectroscop. To estimate the particle size of the obtained materials, transmission electron microscopy was used. The object of the study were polymers, that were synthesized in 10-hour and 24-hour reactions. The particle size in the first material was in the range of 3-10 nm, in the second - from 30 to 100 nm.

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