Image Analysis Optimization for Quantifying Nanoparticle Dispersions in Polymer-based Nanocomposites Using Transmission Electron Microscopy (TEM)

2011 ◽  
Vol 1312 ◽  
Author(s):  
Anand S. Badami ◽  
Mark W. Beach ◽  
Stewart P. Wood ◽  
Steven J. Rozeveld ◽  
William A. Heeschen
Keyword(s):  
Particle Size ◽  
Spatial Distribution ◽  
Representative Sampling ◽  
Nanoparticle Dispersions ◽  
Cumulative Volume ◽  
Transmission Electron ◽  
Large Numbers ◽  
Distribution Parameters ◽  
Uniform Domains ◽  
Dispersion Quality

ABSTRACTWhen comparing large numbers of TEM micrographs of insoluble additives in polymer-based nanocomposite systems, the ability to determine or estimate the dispersion quality (i.e. uniformity of size and/or spatial distribution) is often difficult. The objective of this study was to develop a method to quantify dispersions observed in TEM micrographs that enables both a numerical “ranking” to be assigned to individual dispersions as well as tabulation a multitude of images acquired over time. Several methods were reviewed and applied to a set of TEM dispersion images of an insoluble additive in polystyrene. Projected area diameter, particle area, and Euclidean distance between particle centroids were chosen from all the particle size distribution and spatial distribution parameters present in the literature, but none successfully yielded a quantitative indicator of dispersion quality for the micrographs. In contrast, generating cumulative volume percent curves for each sample appeared to be a preferred method of quantifying and comparing dispersions in TEM micrographs. The volume diameter values obtained by this method can be used for “ranking” and tabulation of dispersion quality and account for both “good” additive dispersions (i.e. those with small domains of a narrow size range around 1 μm or less) and “bad” additive dispersions (i.e. those with non-uniform domains ranging in size by several microns or more). As a result, the numerical values generated by this method can be used to quantitatively determine correlations between the dispersion quality of nanoparticles in polymer-based nanocomposite materials and various macroscale physical and/or performance properties of such materials. This method’s precision was statistically determined to decrease with increasing particle size and be heavily dependent on representative sampling.

Microstructure Characterization of Ag Nanoparticles Prepared by Hydrothermal Method

2012 ◽  
Vol 476-478 ◽  
pp. 1138-1141
Author(s):  
Zhi Qiang Wei ◽  
Qiang Wei ◽  
Li Gang Liu ◽  
Hua Yang ◽  
Xiao Juan Wu
Keyword(s):  
Crystal Structure ◽  
Particle Size ◽  
Hydrothermal Method ◽  
Ag Nanoparticles ◽  
Average Particle Size ◽  
Average Particle ◽  
Face Centered Cubic ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Face Centered

Ag nanoparticles were successfully synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively. The samples by this process were characterized via X-ray powder diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption equation, transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED) to determine the chemical composition, particle size, crystal structure and morphology. The experiment results indicate that the crystal structure of the samples is face centered cubic (FCC) structure as same as the bulk materials, The specific surface area is 24 m2/g, the particle size distribution ranging from10 to 50 nm, with an average particle size about 26 nm obtained by TEM and confirmed by XRD and BET results.

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.

Effect of Synthesis Temperature on Particles Size and Morphology of Zirconium Oxide Nanoparticle

2017 ◽  
Vol 50 ◽  
pp. 18-31 ◽  
Author(s):  
Rudzani Sigwadi ◽  
Simon Dhlamini ◽  
Touhami Mokrani ◽  
Patrick Nonjola
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Zirconium Oxide ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Crystallite Sizes ◽  
Ft Ir

The paper presents the synthesis and investigation of zirconium oxide (ZrO2) nanoparticles that were synthesised by precipitation method with the effects of the temperatures of reaction on the particles size, morphology, crystallite sizes and stability at high temperature. The reaction temperature effect on the particle size, morphology, crystallite sizes and stabilized a higher temperature (tetragonal and cubic) phases was studied. Thermal decomposition, band structure and functional groups were analyzed by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Thermo-gravimetric analysis (TGA) and Fourier transform infrared (FT-IR). The crystal structure was determined using X-ray diffraction. The morphology and the particle size were studied using (SEM) and (TEM). The shaped particles were confirmed through the SEM analysis. The transmission electron microscopic analysis confirmed the formation of the nanoparticles with the particle size. The FT-IR spectra showed the strong presence of ZrO2 nanoparticles.

scholarly journals Distribution of Bacillus thuringiensis subsp. israelensis in Soil of a Swiss Wetland Reserve after 22 Years of Mosquito Control

2011 ◽  
Vol 77 (11) ◽  
pp. 3663-3668 ◽  
Author(s):  
Valeria Guidi ◽  
Nicola Patocchi ◽  
Peter Lüthy ◽  
Mauro Tonolla
Keyword(s):  
Spatial Distribution ◽  
Bacillus Thuringiensis ◽  
Confidence Interval ◽  
Quantitative Pcr ◽  
Mosquito Control ◽  
Soil Samples ◽  
Sampling Point ◽  
Content Type ◽  
Large Numbers ◽  
Continuous Accumulation

ABSTRACTRecurrent treatments withBacillus thuringiensissubsp.israelensisare required to control the floodwater mosquitoAedes vexansthat breeds in large numbers in the wetlands of the Bolle di Magadino Reserve in Canton Ticino, Switzerland. Interventions have been carried out since 1988. In the present study, the spatial distribution of restingB. thuringiensissubsp.israelensisspores in the soil was measured. TheB. thuringiensissubsp.israelensisconcentration was determined in soil samples collected along six transects covering different elevations within the periodically flooded zones. A total of 258 samples were processed and analyzed by quantitative PCR that targeted an identical fragment of 159 bp for theB. thuringiensissubsp.israelensis cry4Aaandcry4Bagenes.B. thuringiensissubsp.israelensisspores were found to persist in soils of the wetland reserve at concentrations of up to 6.8 log per gram of soil. Continuous accumulation due to regular treatments could be excluded, as the decrease in spores amounted to 95.8% (95% confidence interval, 93.9 to 97.7%). The distribution of spores was correlated to the number ofB. thuringiensissubsp.israelensistreatments, the elevation of the sampling point, and the duration of the flooding periods. The number ofB. thuringiensissubsp.israelensistreatments was the major factor influencing the distribution of spores in the different topographic zones (P< 0.0001). These findings indicated thatB. thuringiensissubsp.israelensisspores are rather immobile after their introduction into the environment.

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.

scholarly journals Synthesis of Nano Chitosan as Carrier Material of Cinnamon’s Active Component

2018 ◽  
Vol 21 (2) ◽  
pp. 92-97 ◽  
Author(s):  
Ngadiwiyana Ngadiwiyana ◽  
Enny Fachriyah ◽  
Purbowatiningrum Ria Sarjono ◽  
Nor Basid Adiwibawa Prasetya ◽  
Ismiyarto Ismiyarto ◽  
...  
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Chitosan Nanoparticles ◽  
Dual Function ◽  
Ftir Analysis ◽  
Natural Polymer ◽  
Mild Conditions ◽  
Natural Extracts ◽  
Deacetylation Degree ◽  
Transmission Electron

Development and innovation to improve the efficacy of active ingredients of a plant can be done by using nanoparticle encapsulation of chitosan, which has dual function of protecting natural extracts degradation and delivering natural extracts to the target site. Chitosan is a natural polymer that is nontoxic, mucoadhesive, biodegradable, and biocompatible. This polymer also has a low level of immunogenicity and can be prepared into nanoparticles in mild conditions that make it suitable for natural extracts delivery systems. This paper reported synthesis of chitosan nanoparticles for cinnamon’s natural extract delivery. Chitosan synthesis was carried out by chitin deacetylation isolated from shrimp shells. Chitosan characterization was done by measuring deacetylation degree by FTIR. Chitosan nanoparticles were prepared by ionic gelation method using tripolyphosphate as crosslinker. Morphology and particle size of nano chitosan were characterized using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The result found that the yield of deproteinated chitin was 62.60%. Further process of demineralization resulted a yield of 52.60%, then depigmentation with a yield of 75.56%, and deacetylation with a yield of 79.02%. FTIR analysis showed that deacetylation degree of chitin into chitosan was found of 87.78%. Characterization by SEM found that nano chitosan has a particle size of 87 nm. While TEM images showed that the nano chitosan has a uniform shape and a lower physical aggregation.

scholarly journals Biosynthesized gold nanoparticles-doped hydroxyapatite as antibacterial and antioxidant nanocomposite

2021 ◽  
Author(s):  
Is Fatimah ◽  
Putwi Widya Citradewi ◽  
Amri Yahya ◽  
Bambang Nugroho ◽  
Habibi Hidayat ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Antioxidant Activity ◽  
Particle Size ◽  
Gold Nanoparticles ◽  
Antibacterial Activity ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging

Abstract The composite of green synthesized gold nanoparticles (Au NPs)-doped hydroxyapatite (HA) has been prepared. The gold nanoparticles were produced via bioreduction of HAuCl4 with Clitoria ternatea flower extract, and utilized in the synthesis of hydroxyapatite using Ca(OH)2 and ammonium diphosphate as precursor. The aim of this research is to study the structural analysis of the composite and antibacterial activity test toward Eschericia coli, Staphylococcus aureus, Klebsiela pneumoniae, and Streptococcus pyogenes. In addition, the antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method. The monitoring of gold nanoparticles formation was conducted by UV–vis spectroscopy and particle size analyses, meanwhile the synthesized composite was studied using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that homogeneously dispersed gold nanoparticles in HA structure was obtained with the particle size ranging at 5-80 nm. The nanocomposite demonstrated antibacterial activity against tested bacteria. The nanocomposite expressed an antioxidant activity as shown by the DPPH scavenging activity of 66 and 58% at the concentration of 100 μg/mL and 50 μg/mL, respectively.

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