Particle size determinations in colloidal suspensions of randomly oriented ellipsoids

2007 ◽  
pp. 145-150 ◽  
Author(s):  
A. Quirantes ◽  
A. V. Delgado
Keyword(s):  
Particle Size ◽  
Colloidal Suspensions

PREPARATION OF TIN OXIDE NANOPARTICLES BY LASER ABLATION IN SOLUTION

2006 ◽  
Vol 05 (02n03) ◽  
pp. 259-264 ◽  
Author(s):  
MEI LI ◽  
QINGHUA LU ◽  
ZONGGUANG WANG
Keyword(s):  
Particle Size ◽  
Laser Ablation ◽  
Aqueous Solutions ◽  
Tin Oxide ◽  
Pure Water ◽  
Sodium Dodecyl ◽  
Colloidal Suspensions ◽  
Chemical Components ◽  
Oxide Nanoparticles ◽  
Tin Oxide Nanoparticles

Tin oxide nanoparticles with a narrow size distribution were prepared by pulsed laser ablation of a pure tin target both in aqueous solutions and in pure water. Laser beam of 266 nm, 355 nm and 532 nm from an Nd :YAG laser were applied and the wavelength effects on preparation of tin oxide particles were examined. The particle size and phase structure were characterized by using transmission electron microscope (TEM). The observation revealed that the particle size of the nanoparticles was about 2–5 nm. Chemical components of obtained nanoparticles were analyzed by using an energy dispersive X-ray analysis (EDX) and the results demonstrated that the nanoparticles mainly consisted of Sn and O elements. Furthermore, aqueous solutions of sodium dodecyl sulfate (SDS) were used to study the influence of surfactant concentration on the formation of tin oxide nanoparticles. When the surfactant reached critical micelle concentration, relatively stable colloidal suspensions consisting of well-dispersed tin oxide nanoparticles were obtained. UV-vis spectrometer was used to measure the absorption of suspensions of tin oxide nanoparticles.

scholarly journals Spatially and angularly resolved spectroscopy for in-situ estimation of concentration and particle size in colloidal suspensions

2017 ◽  
Vol 409 (30) ◽  
pp. 6975-6988 ◽  
Author(s):  
Yi-Chieh Chen ◽  
David Foo ◽  
Nicolau Dehanov ◽  
Suresh N. Thennadil
Keyword(s):  
Particle Size ◽  
Colloidal Suspensions

Phase equilibrium of colloidal suspensions with particle size dispersity: A Monte Carlo study

2009 ◽  
Vol 130 (19) ◽  
pp. 194902 ◽  
Author(s):  
Marianna Yiannourakou ◽  
Ioannis G. Economou ◽  
Ioannis A. Bitsanis
Keyword(s):  
Particle Size ◽  
Monte Carlo ◽  
Phase Equilibrium ◽  
Colloidal Suspensions ◽  
Monte Carlo Study

scholarly journals Effect of ultrasonication on the size distribution and stability of cellulose nanocrystals in suspension: an asymmetrical flow field-flow fractionation study

Cellulose ◽  
2021 ◽  
Vol 28 (16) ◽  
pp. 10221-10238
Author(s):  
Christoph Metzger ◽  
Roland Drexel ◽  
Florian Meier ◽  
Heiko Briesen
Keyword(s):  
Particle Size ◽  
Light Scattering ◽  
Flow Field ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Cellulose Nanocrystals ◽  
Colloidal Suspensions ◽  
Field Flow Fractionation ◽  
Ultrasound Energy ◽  
Flow Fractionation

AbstractCellulose nanocrystals (CNCs) are bio-based building blocks for sustainable advanced materials with prospective applications in polymer composites, emulsions, electronics, sensors, and biomedical devices. However, their high surface area-to-volume ratio promotes agglomeration, which restrains their performance in size-driven applications, thereby hindering commercial CNC utilization. In this regard, ultrasonication is commonly applied to disperse CNCs in colloidal suspensions; however, ultrasonication methodology is not yet standardized and knowledge of the effects of ultrasound treatments on CNC size distribution is scarce. The major goals of this study were attributed to targeted breakage of CNC agglomerates and clusters by ultrasound. The evolution of particle size distribution and potential de-sulfation by ultrasonication as well as the long-term stability of ultrasonicated CNC suspensions were investigated. Colloidal suspensions of sulfated CNCs were isolated from cotton α-cellulose. Effects of ultrasonication on particle size distribution were determined by asymmetrical flow field-flow fractionation (AF4) coupled with on-line multi-angle light scattering and ultraviolet spectroscopy. These results were complemented with off-line dynamic light scattering. High ultrasound energy densities facilitated cumulative dispersion of CNC clusters. Consequently, the mean rod length decreased logarithmically from 178.1 nm at an ultrasound energy input of 2 kJ g−1 CNC to 141.7 nm (− 20%) at 40 kJ g−1 CNC. Likewise, the hydrodynamic diameter of the particle collective decreased logarithmically from 94.5 to 73.5 nm (− 22%) in the same processing window. While the rod length, below which 95 wt% of the CNCs were found, decreased from 306.5 to 231.8 nm (− 24%) from 2 to 40 kJ g−1 CNC, the shape factor of the main particle fraction ranged from 1.0 to 1.1, which indicated a decreasing number of dimers and clusters in the particle collective. In summary, progressing ultrasonication caused a shift of the particle length distribution to shorter particle lengths and simultaneously induced narrowing of the distribution. The suspension’s electrical conductivity concurrently increased, which has been attributed to faster diffusion of smaller particles and exposure of previously obscured surface charges. Colloidal stability, investigated through electrical AF4 and electrophoretic light scattering, was not affected by ultrasonication and, therefore, indicates no de-sulfation by the applied ultrasound treatment. Occurrence of minor CNC agglomeration at low ultrasound energy densities over the course of 6 months suggest the effect was not unmitigatedly permanent.

Sign in / Sign up

Export Citation Format

Share Document