Where to put the carbon?

You may have seen a few articles lately about a nuisance of a chemical called carbon dioxide, namely, that it's the waste product of a number of very common chemical reactions and doesn't itself react with much (other than plants, but that reaction isn't fast or extensive enough to keep up with our current production rate) meaning it accumulates in the environment.

So, we're trying to make sure less of it gets into the environment. One class of methods which you may have heard of is carbon capture and sequestration, where after production it's captured, compressed, and often pumped deep underground—sometimes into retired oil wells, sometimes into the deep ocean, or many other places.

Before it can be stored, however, it has to be captured. Scrubbing can be highly effective at removing CO2 from smokestacks and other concentrated sources, traditionally with amine solutions. Then there was a new discovery about the CO2 absorption of polyethylenimine, which was what caused me to start researching this post.

One of the issues with a reaction that is very effective at grabbing a chemical out of the air is making it let go again. Most of the chemicals that are good at grabbing CO2 are too expensive to use only once. Polyethylenimine is of great interest because it releases the CO2 easily by heating it up, which can let the CO2 be collected in concentrated form for use elsewhere.

Overflowing with math

New toy!

After discussing the options with one of my co-workers, I installed SciPy and all its associated dependencies, because it was free and had more than enough computational power to do what I wanted to play with. I don't know enough about any of the computer-math programs to make a case for work buying me one of the very expensive programs, and I couldn't rationalize buying such a program for myself at home to play with, so open source it is.

My first "project", such as it was, was both somewhat practical and relevant to my work, while still being easy enough for a first project: calculating how long it takes for the flow to reach steady state in a series of tanks with a pump at one end (step change input) and gravity flow all the way through.

Chemical wires

For the ever-shrinking world of micro-electronics, I hear the size of the wires themselves are a tricky problem to handle. For one thing, how do you place and solder a wire that's only a dozen atoms across? I don't work in micro-electronics (or any kind of electronics) so that's all I'll say about that.

However, a new nanowire has recently been connected between two tiny electrodes. It's so tiny it can only be seen under an atomic force microscope, and this is what it (well, a whole series of them) looks like:

They conduct nearly as well as copper, and made extremely low-resistance contact with the electrode surfaces they're connecting. Even better? They're self-assembling with an easy to control "on" switch, and charging the electrodes before triggering the self-assembly means the wires build themselves between the charged electrodes and nowhere else.