Particle Analysis of Particle Analysis of Transmission Electron Transmission Electron

Microscopy Microscopy ImagesImages

NYCRI Student Researcher- Divya KrishnaNYCRI Student Researcher- Divya Krishna

NASA Mentors- John DaPonte Ph.D.NASA Mentors- John DaPonte Ph.D.

Thomas SadowskiThomas Sadowski

Team Members – Monica Sawicki, Lisa Marinella, Paidemwoyo MunhutuTeam Members – Monica Sawicki, Lisa Marinella, Paidemwoyo Munhutu

Nanotechnology Nanotechnology [1][1]

1x 101x 10-9 -9 meters (one billionth of a meter) meters (one billionth of a meter) A Human Hair is about 80,000 nanometers wide.A Human Hair is about 80,000 nanometers wide. The nail on your little finger is about ten million nanometers across.The nail on your little finger is about ten million nanometers across.

The material’s optical, electrical, mechanical, and chemical properties change at such The material’s optical, electrical, mechanical, and chemical properties change at such minute sizes. minute sizes.

For Example - When aluminum is shrunk to about 20 – 30 nm it explodes thus For Example - When aluminum is shrunk to about 20 – 30 nm it explodes thus making it ideal to add to rocket fuel. making it ideal to add to rocket fuel.

Effects of Nanotechnology include Effects of Nanotechnology include Stain-resistant nanopants made from fibers treated with fluorinated Stain-resistant nanopants made from fibers treated with fluorinated

nanopolymer.nanopolymer. Spheres of silica, coated with a thin layer of gold and are about 120 Spheres of silica, coated with a thin layer of gold and are about 120

nanometers, can infiltrate tumors when injected through a bloodstream.nanometers, can infiltrate tumors when injected through a bloodstream. Crude oil filter made from a white layer of zeolite nanocrystals that filters crude Crude oil filter made from a white layer of zeolite nanocrystals that filters crude

oil into diesel fuel. oil into diesel fuel.

TEMTEM(Transmission Electron (Transmission Electron

Microscope)Microscope) Creates a bright field image as electrons are transmitted through a Creates a bright field image as electrons are transmitted through a

sample which is under a vacuum. sample which is under a vacuum. Electrons have wave properties which are small enough to detect Electrons have wave properties which are small enough to detect

nanoparticles vs. light waves which have a much higher nanoparticles vs. light waves which have a much higher wavelength. wavelength.

The electrons are shot down through a The electrons are shot down through a

magnetic field until some of them magnetic field until some of them

penetrate through the sample. penetrate through the sample. The final image shows darker regionsThe final image shows darker regions

where the electrons did not go throughwhere the electrons did not go through

and lighter regions where the electronsand lighter regions where the electrons

were absorbed into the sample.were absorbed into the sample.

Project OverviewProject Overview Platinum nanoparticle images were analyzed through an imaging software called ImageJ [2] to Platinum nanoparticle images were analyzed through an imaging software called ImageJ [2] to

find particle size and size distribution. find particle size and size distribution.

Several pre-processing techniques were experimented with including:Several pre-processing techniques were experimented with including: Rolling Ball AlgorithmRolling Ball Algorithm Pseudo Flat Field Correction Pseudo Flat Field Correction

Reasons for pre-processing include elimination of:Reasons for pre-processing include elimination of: The Haloing effectThe Haloing effect Excess amount of noise Excess amount of noise Image contaminationImage contamination

Several thresholding algorithms were experimented with including:Several thresholding algorithms were experimented with including: Entropy Thresholding [3]Entropy Thresholding [3] Kittler Thresholding [4]Kittler Thresholding [4] Calvart-Riddler Thresholding [5]Calvart-Riddler Thresholding [5]

Difficulties arising with the use of thresholding algorithms include:Difficulties arising with the use of thresholding algorithms include: Erosion of nanoparticles in binary imageErosion of nanoparticles in binary image Expansion of nanoparticles in binary imageExpansion of nanoparticles in binary image Incorrect representation of original particle imageIncorrect representation of original particle image

Original Monomer TEM Image Binary Image

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Original Polymer TEM Image Enhanced Grey Scale Image

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Current & Future StudiesCurrent & Future Studies

Acquiring known specimen images as controls for Acquiring known specimen images as controls for comparing and confirming accurate particle comparing and confirming accurate particle measurements. measurements.

Known specimens- 90 nanometer Latex Spheres.Known specimens- 90 nanometer Latex Spheres. Expansion into nanowiresExpansion into nanowires

Gallium Nitride nanowires Gallium Nitride nanowires Two dimensional analysis: length, width Two dimensional analysis: length, width

Atomic Force MicroscopyAtomic Force Microscopy AFM creates a topographical map of a sampleAFM creates a topographical map of a sample Antimony particles will be analyzed for particle size and Antimony particles will be analyzed for particle size and

distribution.distribution.

ReferencesReferences1.1. Kahn, Jennifer. “Nanotechnology” Kahn, Jennifer. “Nanotechnology” National Geographic, National Geographic, JuneJune, pages , pages

100-119, 2006.100-119, 2006.

2. ImageJ - 2. ImageJ - http://rsb.info.nih.gov/ij/http://rsb.info.nih.gov/ij/

3. J.N. Kapur, P.K. Sahoo, and A.K.C. Wong, “A new method for gray-level 3. J.N. Kapur, P.K. Sahoo, and A.K.C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Graph. picture thresholding using the entropy of the histogram,” Graph. Models Image Process. 29, 273-285 (1985)Models Image Process. 29, 273-285 (1985)

4. J. Kittler and J. Illingworth, “On threshold selection using clustering 4. J. Kittler and J. Illingworth, “On threshold selection using clustering criteria,” IEEE Trans. Syst. Man Cybern. SMC-15, 652-655 (1985) criteria,” IEEE Trans. Syst. Man Cybern. SMC-15, 652-655 (1985)

5. T.W. Ridler and S. Calvard, “Picture thresholding using an iterative selction 5. T.W. Ridler and S. Calvard, “Picture thresholding using an iterative selction method,” IEEE Trans. Syst. Man Cybern. SMC-8, 630-632 (1978)method,” IEEE Trans. Syst. Man Cybern. SMC-8, 630-632 (1978)