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Announcing Sacred Mounds, a novel of Magical Realism and Historical Fantasy from Jim Metzner, with a foreword by Hutke Fields, principal chief of the Natchez Nation.
Cyclonic hordes of insects, a telepathic despot, body-swapping sex - just a few of the surprises Salvador Samuels encounters when he is swept back to pre-colonial times, walking in the moccasins of a blind Indian - who, in turn, has been transported into Salvador's body in present-day America. Sacred Mounds Book Cover Four hundred years apart, they are bound by a mission to rescue our world, aided by the mysterious presence of the mounds. Thousands of these ancient earthworks once dotted the landscape of North America. We still don't know why they were created. Sacred Mounds suggests they are as important today as when they were made over a thousand years ago. Sacred Mounds weaves the stories of two men, each a stranger in a strange land. With the help of two remarkable women, they must find a way to save our planet and return home.
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Material Science - Silly Putty: The Pulse of the Planet daily radio program offers free legal online mp3 downloads, exploring the world of sound in nature, culture and science, with audio adventures, world music, extraordinary sound portraits, science diaries, and nature ring-tones; an amazing sonic experience.



Airdate: Nov 02, 2010
Scientist: Dr. Daniel A. Savin

Material Science - Silly Putty

Material Science - Silly Putty
Silly Putty - is a liquid or a solid?

Transcript:
music

You remember Silly Putty a science toy we all grew up with. Would you say it's a liquid or a solid? I'm Jim Metaner and this is the Pulse of the Planet. Daniel Savin is an assistant professor at the University of Southern Mississippi.

DS: So what happens to the silly putty when I drop it? It bounces back up to my hand. So over short times it behaves like a solid.

DS: But I can also take the silly putty and I can start to stretch it out like taffy. And if I stretch it out like taffy slowly it'll just keep stretching as long as I'm pulling. But if I take the same silly putty and I rub it back together and I pull on it quickly, what do you think is gonna happen? It breaks in 2 pieces. So it behaves like a solid over short times but it behaves like a liquid over long times. In fact I could take these 2 edges and put them back together and I could start to pull on it again. And it doesn’t break it behaves as if that break never happened.

DS: Silly putty like all polymers behaves differently over different time scales. We're gonna take some pieces of the silly putty, and we're gonna hit it with a hammer and we're gonna see what happens. So Silly behaves like a solid over short times - What do you think would happen if you took an ice cube and hit it with a hammer? Well it would probably do the same thing. But could you take an ice cube and form it into a ball and have it be a nice rubbery ball that bounces? And then stretch it out? You certainly would not be able to do that with ice but this is something you can do with polymers.

Besides Silly Putty, there are many kinds of polymers with many different special properties and they're all part of the palette of materials that a materials scientist works with. Materials science is one of the science topics in this year's Kids Science Challenge our free nationwide competition for 3rd to 6th graders; check out kidsciencechallenge.com. Pulse of the Planet is made possible by the National Science Foundation. I'm Jim Metzner.