Daina Fri, 26 Mar 2010:I found a local expert on nano-clays. I won't name names, because unfortunately, I had a very difficult time getting across our idea of achieving integration of this problem/idea into the undergrad curriculum. But this might work out anyway . . . . A group of faculty have already been working on undergraduate education in nanotechnology. If you check out this web site (http://www.egr.msu.edu/nue-tpn/), it already contains a slew of educational information that can be used by freshmen through seniors. ChE seniors already have a laboratory experiment in which they test the properties of various polymer films containing nano-clay particles. Apparently clays are very difficult to work with, so the experiments involve the students using pre-fabricated films with certain types of nano-clays already included. The web site also has a simple simulation that demonstrates how a particular property (e.g., conductivity) changes with the amount of nano-clay loading in a polymer, in this case nylon, I think. So there is also something already for freshmen to do. So the basic ideas behind the problem are * nanoclays can be exfoliated so that the "stacks" of clay are I learned a lot, but now I'm tired of typing "disaggregated" so
that's it for now! I'm not sure of what kinds of questions we can ask
Cascade, because according to our resident expert, they are
oversimplifying the problem in the wrong directions. Daina Thu 04-01-10: If you are in the meeting and can read this message, here are a few 1. What is the objective of exfoliating the nano-clays? What properties 2. Is 100% exfoliation desirable for this 'property' that you obtain from 3. What is the trade-off between exfoliating and breaking the nano-clay 4. What would be the cost of obtaining nano-clays and suitable polymers to 5. The energy of exfoliation also depends on the suspension density, These are just starters. Tom Mon, 29 Mar 2010:I took a look at all three problems. In each case, the general concept of the problem (why it is a problem) can be grasped, but in all three cases, students would need to have a governing set of equations, definitions of properties, etc. to define the problem. I then Googled bio sand filters and the first link took me towww.biosandfilter.org. There is voluminous information here, but it didn't appear to be in a form where a student could take a set of governing equations and parameter values and build a model. Then went to the Wikipedia entry, and at least quickly found a cross-section of one. What is needed MAY be in the biosandfilters.org site, but there was so much there that the time to find what is needed to build a model for a homework problem would be disproportionate to building the model. I see problems 1 and 3 in the same vein. #1 Separating nanoclay layers -- how much energy is needed? Where would I go to get governing equations and parameters to model the separation process? Would those equations be mechanistic or empirical? #3 Roof structures. This one could be worked by freshmen without Physics I or Statics IF you essentially gave them what they needed, and constrained the problem (e.g. defining the type of roof, where the load might be, etc.) Otherwise, they couldn't likely deal with point and distributed loads, moments and shear, bending stresses in beams, truss analysis (many real roofs are steel joist trusses), and they would need to avoid concrete or composite structures at all costs. My thoughts on "authentic problems" for modeling remain the typical problems we often see in regular classes (they have stood the test of time), but represent REAL processes and products, and are not just made up numbers to put in equations. Statics books typically have many good examples, such as crane loadings. My two cents. Neeraj Wed Mar 30, 2010:Comments on Problem 3 I agree with Tom that no Physics or Statics knowledge is needed. This is a problem in bookeeping, i.e. making sure that all loads (dead, live, snow, wind.....) have been accounted for. Depending on the roof type and material access to appropriate code or codes will need to be given to the students. |