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mjdwyer23
Jul26-04, 07:36 PM
Hi everyone-
I'm a junior at U. Penn doing a research project on thermal expansion in complex perovskites. I'm having trouble with a computer program that I'm using to control and obtain data from our dilatometer. The problem is that the software was made in the mid to late 80's, and it only gives data in ppm. What I need to do is convert the expansion to a percent. The program, however, seems to not measure the original length at all. It looks like it tares the sensor at the programmed reference temperature and goes from there, but the alpha (thermal expansion coefficient) needs to be calculated with the original length. Is there any way I can convert from ppm to cm to get a percent change somehow? Thanks

Matt Dwyer

enigma
Jul27-04, 01:42 AM
ppm (parts per million) is short-hand for a strain of 1x10-6 [length/length].

If you need more than that, just ask.

enigma
Jul27-04, 01:50 AM
This thread is a duplicate from here (http://www.physicsforums.com/showthread.php?t=36803)

I'm going to close this one.

mjdwyer, in the future, please only post your question in one place. It's easier to have a coherent conversation that way. If the post is better suited for another forum, the mentors will move it for you.

Welcome to PF, btw!