Monday, July 15, 2013

Summer 2013: Day 6

Dan Neumann welcoming the teachers
Juscelino Leao talking about making neutrons.
There is no better way to start of a week then with a nuclear reactor. Today was our visit to NCNR, The NIST Center for Neutron Research. It was really amazing. Dan Neumann welcomed us out to the center and then Juscelino Leao talked with us about Making Neutrons. He talked about the nuclear reactor and how it is designed specifically to minimize heat and maximize the number of neutrons produced. When running, it produces 1011 neutrons neutrons per cm2 per second. They did a chain reaction demo using ping pong balls and mouse traps similar to the one seen below.

He also had a lot of questions about safety. Luckily, with all that radiation, there are very strict safety procedures in place. One year working at NCNR is less radioactive exposure than being on a flight from New York to Los Angeles, and about 5 x-rays. We also learned about the barn, which is the unit for the chance neutrons will hit an atom.
On the tours
We went on tours where we visited with six different scientists. They talked about the equipment and how it can be used to understand neutrons or different properties of materials. One of the cool labs was where they characterized fluids, and they gave us a sample of a shear thickening liquid. It looks a little like water, but after it is shaken, it turns in to a gel. It was amazing to see all the different things that can be done with neutrons.

After the first tour, we went back to the classroom to grow crystals. The most difficult part was tying a string around the seed crystal. After making an over-saturated solution in warm water, the containers were set aside, and the crystals would grow for the rest of the week. Hopefully, they will turn out.

Michael looking at the end goal.

Nichole getting help on the solution.

Laura checking that the concentration is right.

And then we wait.
We also talked about diffraction, specifically diffraction through crystals. The patterns seen, when shining a laser or neutron source through a material, can determine the molecular structure of that material. This is especially important in material science. Understanding different molecular structure has potential applications in development of new materials.
Jerry looking at a diffraction pattern.
The day was also full of classroom tools or "toys" as they are sometimes called. Everyone got a laser and diffraction gratings, optical fiber wands, luggage scales, choose-it balls, and the invisible bead jars. They were all great demonstrations of the work done at NCNR and have applications in the classroom.


  1. The ping pongs ball had me contemplating what I wanted to use this exercise for in my class. I learned so much about crystals and I can't wait to use the crystal exercise in my classroom. Awesome day.

  2. Wow, that mouse trap video is really cool!

  3. Big J rocked it! THe tour of the neutron lab was fantastic!