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In March I went to Denver, CO for the APS Physics Conference known as The March Meeting. Roughly 6,000 people were there during the 2nd week of March to watch and deliver talks on their latest work in Physics. It was really intense. I would wake up really early everyday to get to the talks, and then all day you'd be talking to people or watching tons of talks. Then at night I'd hang out with old friends from other schools that I would never get to see otherwise. Then we'd stay up even later and either watch other people practice their talks or I'd practice my own talk. Or just look up what talks that I planned on going to the next day. It was really intense. And the best part was that I brought my snowboard and went riding all day on Tuesday and Saturday. It was the best snowboarding I'd ever done. Definitely have to get back there. Unfortunately I'm lame and I don't have any kind of digital camera, so I don't have any pictures from the snowboarding. One of these days I'll have to get a camera. The picture on the right was taken by another graduate student. Even though we were staying at a four star hotel, we had to pay for wireless internet access, which sucked. However, if you sat by the window you were barely within reach of any number of Wifi spots, such as the free Wifi provided by Denver's 16th street.


My final exam stuff ended on May 10th, at which point I flew away to hang out with some friends. Since then I've been working non-stop on my qualifier, which will be on August 3rd. I have to make a research proposal in front of a committee on this new research experiment that I've developed. It's pretty cool, and I'll write more about it after I'm done. But for now, here's a neat picture of the types of particles that I propose on using in my project. This picture is from the web page of David Pine at the New York University. They were the ones who made the clusters seen in the picture here. You can check out their page here: http://physics.nyu.edu/pine/research/clusters.html

Both times we have synthesized colloids we witnessed an "explosion", or more accurately, an eruption during the reaction. We would cook the sample at 80 degrees C for a few hours to dissolve the solvents, polymer, and other reactants. Upon adding more solvent and raising the temperature to 140 degrees, there would be a spontaneous and surprising eruption of our solution. Friday's explosion wasn't as large as last Thursday's, where the eruption was so great that the solution was actually sprayed all over the sides and floor of the fume hood.

On Friday, when it erupted again, I noted that the temperature of the solution at this time was 102 degrees, while the temperature of the oil bath was actually 140 degrees. Since we have a condenser attached to the vial where the solution is, nothing is able to evaporate. Specifically, our solution heats up, evaporates, and then the vapor rapidly condenses within the condenser and drips back into the solution. Since the condenser is open to the room, we are able to heat up our solution without increasing the surface pressure.

the cause:
Anyways, 100 degrees is the boiling point of water. Since our oil bath was at 140, and our solution hung at around 100 degrees for a moment, we believe that there are trace amounts of water in our chemical solution. Perhaps from condensation in the room while assembling the apparatus. Regardless, we were super-heating the water, which then resulted in the spontaneous vaporization of all the water in the sample.

The first time, we only rinsed our glasswares with soap and water, and then alcohol. This time we baked them for a few hours in the oven after cleaning. The oven bake must have vaporized most of the water, which is why the eruption was smaller the second time around.

possible solution:
The next time we attempt this experiment, we will try and cause the eruption with only the solvents, before beginning the experiment. We will cook the hexane and dodecane at 140 degrees, and see if we can cause the eruption before we begin seeding the reaction.

final thoughts:
Also, I think that the eruption might play a role in the polydispersity of our beads. Another factor may be the shaking of the apparatus. During the experiment, using a paper-clip as our stir-rod, we stir the oil in the oil-bath to create a more even heat distribution. However, the motion of the oil must be causing the vials to gently shake. It would be ideal, in my mind, to have no shaking at all. We'll see if we can find a solution to that.