The actinometry study was done for the past week and a half with the help of the team we managed to find great data and let’s just say Dr. Sebree was extremely excited. Actinometry is a study that determines the number of photons in a beam. We started by setting up the actinometry chamber and hooked it up to a tank of dinitrogen monoxide (laughing gas) and a thermometer to the side of the chamber.
Our portable actinometry chamber
The chamber was filled to a pressure the pressure and temperature were then recorded as soon as the lamp was turned on. Each run was done for 10 minutes in those ten minutes all I had to do was make sure the chamber was running and stop it at the correct time. After the run was finished the temperature and pressure were recorded and used to find the photons emitted by the lamp.
Lamps with benzene films coating them
We used several different lamps for this at different life spans in order to determine how much the time amount of hours used affects the photons emitted by the lamp. We also compared dirty vs clean lamps by letting the lamps run for 20 hours after calculating it when it was clean. This simple but effective study gave us great data and Dr. Sebree will be presenting this at the Iowa Academy of Science conference.
These past months have been a wild ride for the team working with Dr. Sebree. Myself, along with Carissa, Jose, and Steven, have radically changed the lab we were working in.
To start, we have installed a new spectroscopy chamber. This chamber will be an entirely closed system under vacuum pressure. The reason for the closed system is to have the chamber sit inside an IR spectrometer and so we can identify and analyze the molecules that are in our aerosols without the risk of atmospheric contamination. Molecules will show up with a signature on a spectra to mark its presence based on the light absorbed by it. After each run through the chamber, the system will be heated to burn off anything in it and be deposited at the bottom of the ion pump. Simple enough, right? You just need to have minute amounts of aerosol running through a chamber with windows and make sure it all gets sucked into the ion pump! The process getting to this point was not quite so simple.
New chamber built by the team
First of all, we had to build the chamber. The involved taking spare parts with openings and ends that would be useful in our system. To actually screw the parts together was a 2-3 person job. 1-2 people holding the chamber and the other using a ratchet wrench to get it properly sealed. Once all the pieces were together we ran into a few problems. The current setup of the lab was not conducive for working on the system.
The previous set-up that has become less cluttered since the picture was taken
The spectrometer needs to be cooled with liquid nitrogen daily which limited where the chamber could be located, and finally, it needed to be near the computer and monitor so we could monitor the readings. After some creative problem solving, we found tables to use. After that was the fun part! Dr. Sebree, Jose, and myself all worked together to to move the new chamber and ion pump (all of which was currently under vacuum pressure and could not be opened under any circumstance in order to transport each piece).
New chamber hooked up and ready to be moved/installed
It was a very high pressure situation. Any false move could have ended in catastrophe. Thankfully, with great care and luck, we got the new tables in place that made working on the entire system much more user friendly.
Much less cluttered set-up for the new chamber
The new set-up completed
The new chamber sitting in the spectrometer
Once we get a few more things hooked up, it’ll be ready to start giving us some data to analyze!
The new chamber isn’t the only exciting thing happening in the lab, we are still producing aerosol samples even though we haven’t been analyzing them with the SEM as we previously were, but those will have to wait for a future blog. We still have some work to do, but our part of the project is in a really good spot to where we’ll be able to analyze some results really soon!
On this page we'll post updates of the BETA Project's progress- stay tuned!