A Study of Nanoparticle Aggregation by Coherent Light Scattering

Chicea, Dan

doi:10.2174/157341312800167704

Cited by 23 publications

(38 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This result can be tested using Monte Carlo methods [11]. As described in [11], [27], in a simplified Static Light Scattering experiment, the mentioned function can be used to evaluate the nanoparticles diameters by measuring the anisotropy parameter.…”

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

“…This method is described in [28], [29], [30]. Experiments showing results with this method are described in [27], and [31].…”

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

“…For this purpose the procedure as described here, including the computer codes previously written and used [27], [31] were tested again. The whole set of data that was used to train the Neural Network, the clean input, as described in the next section, was used as input for the Dynamic Light Scattering procedure.…”

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

See 2 more Smart Citations

Using Dynamic Light Scattering Experimental Setup and Neural Networks For Particle Sizing

Rei

Chicea

2017

ACTA Universitatis Cibiniensis

Self Cite

View full text Add to dashboard Cite

Using a Lorentzian function fit as reference, a basic experiment was designed for processing IntroductionThe study of nanoparticles is a topic of major interest in the last decades due to the wide array of applications, especially in the area of biology and medicine. As a consequence of their small size, one order of magnitude smaller than the living cells, they can be used to deliver various substances to living cells, producing, in general, only minor perturbations. The applications of these nanomaterials were presented in several papers, such as [1]. During development of these applications, there were concerns about the toxicity of these methods. As a result, techniques for monitoring the nanoparticles concentration were also developed [2].The properties of the systems of nanoparticles are in direct relation to the size distribution of the particles in the fluid. For this reason, the size characterization of these systems is one relevant aspect for further development of the nanotechnology applications. There are various techniques used for this. One modern technique is the Transmission Electron Microscopy (TEM) which evaluates particles in the range from nanometers to micrometers. This method has a good resolution but is in general expensive, time consuming and does not work in-situ. Another method is the X-Ray powder diffraction which can offer the size distribution of the particles [3]. For metal oxides, for which the assumption used is that the crystallite size is the same as the particle size, the Scherrer equation [4] can offer the mean particle size. For colloidal particles, the Guinier formula [5] can be used in a similar way. However, also these two methods are slow and do not work in-situ. The particle size for nano-systems can also be assessed by the method called "Atomic Force Microscopy" (AFM) [6], [7]. Paper [7] shows a comparison of AFM with TEM. Results show that AFM sizing requires very thin samples over several layers. The samples are scanned line by line and this takes a lot of time. Comparisons and reviews of other techniques used for nanoparticle size characterization are presented in many papers, such as [8]. As in [9], the properties of the nanofluid change very fast during nanoparticle aggregation, and as a consequence, a fast procedure for monitoring the size is needed. A valid option for this are the optical procedures, which use coherent light scattering.The optical methods make use of an incident coherent beam of light which illuminates an active sample volume containing the nanoparticles. Each particle represents a scattering center and becomes a secondary light source. The intensity of the scattered light is anisotropic and depends on the size and shape of the scattering centers. This is described by the phase function, for which there are several models used to represent it [10], [11], [12].If the incident beam is coherent, so are the secondary waves emitted by each scattering center. If a screen or a detector is present, all the wavelets emitted by all the scattering...

show abstract

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

“…This method is described in [28], [29], [30]. Experiments showing results with this method are described in [27], and [31].…”

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

Section: Fig 1 the Schematic Of A Dynamic Light Scattering Experimentsmentioning

confidence: 99%

See 1 more Smart Citation

Using Dynamic Light Scattering Experimental Setup and Neural Networks For Particle Sizing

Rei

Chicea

2017

ACTA Universitatis Cibiniensis

Self Cite

View full text Add to dashboard Cite

show abstract

“…As pointed out in [12] the aggregation process in diluted aqueous solutions is very fast, therefore an alternative solvent must be used for accurate DLS sizing. The time series was analyzed using the DLS procedure described in the next section.…”

Section: Nanofluid Preparation and Characterisationmentioning

confidence: 99%

“…The length of each time slice was set to be 1 second as a compromise to achieve a reasonable quality both for the fit and for the aggregate size time variation. More details on the data processing procedure are presented in [12]. The fitting procedure was repeated for all the consecutive time slices recorded during the experiment in batch mode and the average diameter was calculated for all the time slices of the data series.…”

Section: Dynamic Light Scattering -The Modified Versionmentioning

confidence: 99%

Monitoring nanoparticle aggregation by optical procedures

Chicea¹

2013

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

Abstract. The traditional Dynamic Light Scattering (DLS) produces the average size of the suspended particles from a recorded time series of the light scattered at a particular angle. A modified and simplified version of DLS was designed, tested and used in monitoring FE3O4 nanoparticle aggregation in aqueous suspensions. In addition two another simple and easy to implement optical procedures were tested aiming a qualitative monitoring of the nanoparticle aggregation process. One of them consists of monitoring the time variation of the scattered light intensity at a certain angle and fitting an analytic function on it and the other one in monitoring the refractive index of the aqueous suspension during nanofluid dilution. The results are presented and discussed.

show abstract