Austin Hudson's blog

After making a new soil column I continued with measuring xanthan viscosities as a function of shear rate. The experiment is proceeding much smoother now. Although the results do not exactly match those of the capillary tube, they are very close. 

I'm pretty sure I am not going crazy.

The experiments on the 120-140 sand column continue. Calculated viscosities for the 1g/L xanthan are still ~5 times higher than what was found during the capillary tube experiments. We considered the possibility that the new batch of xanthan solution was improperly mixed, yielding a concentration far greater that used in our calculations. This idea, however, was forsaken after we tested the fluid in the capillary tubes again- the viscosities there agreed with previous experiments in the tubes.

One thing I can say with confidence is that conducting research demands a certain level of patience and dedication that can breed frenzy in even the most sensible people.

Once again, business as usual in the lab. I employ a special concoction of lucky-guess and brute-force methods to measure shear thinning behavior of xanthan solutions. I announce with great excitement that the capillary experiments have, for the most part, reached a conclusion. The soil column, however, continues to illude my greatest efforts to obtain any sensible data.

Good afternoon,

Yet another week has passed, but we haven't aged a day.

Midterms have passed?

Our measured data matches model predictions?

The world is filled with rainbows and gum drops??
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Here we are in week blah, and I could not be happier. On Friday the other interns and I presented the current status of our projects (*Sigh of relief for putting that behind us). It was amazing to see how much progress everyone has made since our first meeting. All of the hard work and suffering seems to have paid off.

Introduction:
Xanthan gum is a polysccharide, derived from the bacterial coat of Xanthomonas campestris. It is also the source of dismay for young scientists, who's only feeble desire is to obtain useful data. See Figure 1 below for an illustration of this phenomenon.

Methods:

So far during my internship all I have done is: read 10 articles discussing NZVI technology, attend a day full of lectures about recent CMOP projects, brave the scrutinous review of the NSF site vist team, stumble my way through using labview to autonomously collect data, conduct rheology experiments for 7 different fluids, redo rheology experiments, and redo rheology experiments. And I thought my summer would be full of excitement...

One word: Wow!

Before starting this internship I did not appreciate the truth of how quickly the first week would pass. There is a false sense of security that comes with having 40 hours to complete one seemingly simple task. And, as with any new adventure, trial and error has become a common theme with my science thus far.

During the next 9 weeks our group (Dr. Rick Johnson, Amanda Mather, and I) will be looking at the transport of particles, such as nanoscale zerovalent iron (NZVI), through granular media (commonly known as sand). Now reader, if you have made it this far in my blog, you may be asking yourself: Why do I care about the movement of particles through sand? To that I would answer that one interesting application is the use of NZVI slurries as an in situ treatment of contaminated groundwater.