A couple of weeks ago, I posted a discoloration array experiment that showed monotonic discoloration patterns here. This was a result that we’d been expecting for several months, but we never got it with NaCl and NaHCO3. Simplifying the solutions to NaCl and NaOH was the key. These results spurred some discussion on the mechanism…
A few weeks ago, we made wafers with three different silicon thicknesses: 15 nm, 30 nm, and 50 nm. The goal was to see how pore morphology changes with increasing thickness. The films were deposited at 450 C with a 25 W substrate bias. The annealing temperature was 800 C in the susceptor. Note that…
Here’s a cropped image from a recent TEM pic that Brian McIntyre took of our material for SiMPore (15 nm thickness, not sure what wafer). This particular feature caught my eye because the crystal is perfectly aligned so we are looking at individual atomic columns of Si, instead of the typical crystal planes. These happen…
The older sepcon macro has been update to fix previous issues and yield more meaningful results. These updates are being brought up to get feedback from the group and from there implement them and make these changes to the newer sepcon patterns and eventually the TEM patterns. Gathering and analyzing statistical data is standard practice…
As mentioned previously, gold colloids are not stable in high salts because salts reduce the repulsive forces between particles and cause aggregation. I have been able to dissolve naked gold colloids in 10mM KCl without aggregation, but the particles crash out at 100mM KCl. There are a couple of strategies that can be used to…
The last few Tecan posts have dealt with adjusting gain values to optimize fluorescent standard curves. We now have a general protocol here, and a final standard curve for fluorescein. Here is the background-reduced standard curve for sodium fluorescein (Na-F) that Christine and I obtained. This was done with the gain set to 0.000125%, and…
I obtained gold in 5nm, 20nm, 40nm, and 60nm through Mort/Oberdorster Lab. Separations were performed with fully crystallized samples from SC 073. Here are sizing and absorbance data: In Water I have tried 24 hour separations in diH2O (SC 073) with these particles. Here are the results: No 525nm peak in filtrate for 5nm sample. …
Our setup copied Jess’s well in a Teflon block. The chips (SCO21) sat over the well filled with 50 ml buffered (pH ~ 6.0) NaCl solution. On top of the well Paul placed a 20 ml drop of the same solution with DNA ladder added. Two types of ladder were used, referred to as a…
I set up separations of 5nm Au nanoparticles in both H2O and KCl in a new system. The stir cell isn’t always reliable for separations due to leaking and contaminating (?) particles from the plastic. To perform these separations, I added 20ul of sample to a sepcon and wetted the backside of the sepcon with…
These are a couple of figures that may appear in the supplementary materials for the permeability paper. The first tries to explain that most of our permeability is due to the largest pores. The lines plotted are the cumulative number of pores at each size (blue) and the cumulative permeability (green). The lines show that…