Dispersion and nanotechnology

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00:00:00 Dispersion and Nanotechnology
00:02:44 Dispersion and nanotechnology
00:02:46 Can I say anything new?
00:03:46 Abstract
00:04:22 The Laws of Physics or The Crunch You call me a crunchie and I’ll take you outside And I’ll show you just how the crunch is applied David Kramer
00:05:20 The 3 S’s
00:06:46 Bulk/Primary: solid bridging; room temperature sintering
00:07:34 Solid-solid diffusion
00:08:49 Gas Phase Particle Growth
00:10:04 Untitled
00:10:39 Inertial and van der Waals forces…..
00:11:48 Bridging will always occur - in the dry state!
00:12:30 Attractive (van der Waals) and inertial forces
00:13:09 Attractive (van der Waals) and inertial forces
00:13:36 Attractive (van der Waals) and inertial forces
00:14:53 Surface and size
00:15:51 Gas adsorption techniques (e.g. BET)
00:16:41 Gas adsorption techniques (e.g. BET)
00:17:03 Using the BET model to measure surface area
00:17:32 Comparison with laser diffraction
00:18:24 Gas adsorption techniques (BET)
00:19:25 Gas adsorption techniques (BET)
00:19:35 Gas adsorption techniques (BET)
00:20:31 Qualitative Measure of Dispersion Efficiency
00:21:45 Surface – the 3 C’s
00:23:15 Surface sensitive techniques
00:24:45 Inverse GC DPI
00:25:41 Differential Polarization Interferometry See: http://www.farfield-scientific.com/pdfs/doubling.pdf And plenty of Webinars…
00:26:20 Differential Polarization Interferometry
00:27:04 Surface Composition/chemistry
00:29:27 TiO2 pigment
00:30:44 TiO2 coatings
00:31:50 The scale of the issue
00:33:33 TiO2 – pictures and plots... Confusing….
00:34:10 So is this reasonable, for example?
00:34:49 Composition
00:36:19 Surface atoms dominate as the size decreases Adapted from: Professor André Nel, Division of Nanomedicine, University of California, Los Angeles http://www.dtsc.ca.gov/TechnologyDevelopment/Nanotechnology/upload/03_Nel.pdf
00:36:44 Nanoclusters See: http://sces.phys.utk.edu/~dagotto/condensed/Magnetic%20Nanoclusters.pdf
00:37:24 Chemisorption induced segregation
00:37:51 Chemisorption induced segregation
00:38:18 Alloys – surface properties
00:39:22 Pd-Au and Pd-Ag alloys
00:40:42 Charge
00:41:40 Zeta potential
00:41:59 Producing a stable dispersion
00:43:31 Titanium dioxide D50 = 0.25 mm approx. Calgon additive
00:44:07 CeO2
00:44:28 Indications that there is a stability issue Removal of ultrasound in DI water - BDAS
00:45:22 Stability studies with Zeta3000HS plus titrator
00:46:47 Stability studies with Zeta3000HS plus titrator
00:47:33 Measurement with optimum conditions Before, during and after ultrasound
00:48:02 Measurement with optimum conditions Before, during and after ultrasound Pre-dispersion (250W u/s 15 minutes) in 0.15% Calgon Measurement in 0.15% Calgon solution
00:48:35 Comparison between properly dispersed and poorly dispersed material
00:48:53 Corona
00:49:39 Skip Rung, President and Executive Director, ONAMI – Blog - referring to recent ILS’s in nano
00:50:25 Powders are also a problem! Kendall
00:51:13 Powder
00:52:30 Adhesion forces - dry milling Theoretical limit of a ball mill
00:53:08 Nanopowder…..
00:53:38 Dissolution
00:54:37 Stress Corrosion Cracking
00:55:24 Tests for “nano”
00:57:42 Settling rates – taken from E2490 Standard Practice Guide for Measurement of particle size distribution of nanomaterials in suspension by Photon Correlation Spectroscopy (PCS) ASTM E56.02
00:58:54 Settling rates - comment
00:59:45 Drexler
01:00:15 K. Eric Drexler
01:00:31 Ladybug - 35mg Elephant – cow – not bull – 3500kg
01:01:11 Heywood – we expect a quote! (Lunar dust)
01:02:26 Thank you
01:05:56 Contact Information
'Nano' is all about small. A dispersed system is smaller than its agglomerated or aggregated precursor. Dr Alan Rawle rambles through the fundamental physical principles outlining dispersion, solid bridging and the importance of the surface