Here’s looking at you

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Everybody played with magnets when they were kids. Iron filings on a sheet of glass. Some engineers never stopped. Today on Engineering Works, we’ll look at how their grownup magnets help doctors figure out what’s wrong when you’re sick.

One of the hardest parts of treating people who are sick is figuring out what’s wrong with them. For centuries, doctors had no good way to find out what’s going on inside of us. X-rays are good at seeing our bones, but not so good at seeing other things.

That’s where MRI comes in. MRI, or magnetic resonance imaging, uses big magnets and powerful magnetic fields to help doctors see the softer parts of our bodies.

But how does MRI do that? It starts with atoms, those tiny particles that make up everything around us. Hydrogen atoms, to be exact. That’s important, because we’re almost all water and water is mostly hydrogen atoms. And, it just happens, hydrogen atoms are what makes MRIs work.

Here’s where it gets tricky, so pay attention. Like all other atoms, hydrogen atoms spin. Like billions of tiny tops, all spinning inside you. When the powerful magnetic field from an MRI machine hits them, they all line up and start spinning in the same direction. With me so far?

Okay. After all the atoms are lined up and spinning, the MRI operator changes things so that the magnetic field slides off the atoms, a thin layer at a time. When this happens, and the atoms stop spinning together, each one blinks out a signal that the MRI machine can record. Powerful computers process these little signals into images that look like fuzzy photographs. Medical specialists can interpret those images just like x-rays. Here’s looking at you, kid.

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Nanomachines

Everybody’s talking about paying attention to the big picture. Today on Engineering Works, we’re going to sketch out some of the tiniest pictures you can imagine.

The big picture is okay, but for some engineers, the tiniest picture you can imagine is what’s important.

The tiny picture these engineers are peering into is full of atoms and molecules. They’re using those atoms and molecules to build things: tiny machines that can do things for us. It’s called nano-technology.

Nanotechnology is going to be important to you. What if your windows cleaned themselves? How about a computer screen thin as a sheet of paper? Tear a tendon? A smart splint tells the cells to heal. Nano-technology can make it happen.

Far-fetched? Not really. Except for the computer screen, all these things are here now. And that’s coming soon. Engineers working in nanotechnology use atoms and molecules to build real-world machines. We’re talking really small engineering here – these parts are about 100-80-thousandths of a human hair across.

Nanotechnology has been around science fiction and Star Trek forever. But it’s not make-believe any more. And in 10 years or so – just like the Internet – nanotechnology will be part of our culture.

This “nano-cultureâ€? will include devices like molecule-size “nanobots,” that seek out and cure disease in our bloodstreams. Nano-machines already exist. A nano-guitar built in 1997 can even be played. So, be on the lookout for more nanotechnology benefits. But look really close.

Making nuclear waste easier to deal with

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Nobody has much good to say about nuclear waste. Well, sit tight. We’re going to talk about just that today on Engineering Works.

When most people hear the words nuclear waste they think of pools of toxic sludge and buzzing geiger counters. But, like everything else, there’s nuclear waste, and there’s nuclear waste.

Nuclear engineers, the folks who have to figure out the best things to do with nuclear waste, look at different kinds of waste differently. Some of it is just bad stuff that needs to be handled carefully and stored safely. And a lot of it can actually end up being useful to us.

For the nuclear waste that emits a lot of radiation, they can use something called transmutation. Transmutation involves bombarding the radioactive waste with high-speed particles from an accelerator to break it up into less hazardous stuff with less radioactivity. This new stuff is less hazardous to move or store than the original waste.

The engineers also have worked out ways to recycle some waste into radioactive products, like medical isotopes, that are useful instead of something to worry about.

And remember, some of the waste comes from nuclear power. That gives us almost a quarter of the electricity we use in the Untied States. So stop and think the next time someone says something about radioactive waste. It can still be a problem, but engineers are coming up with new ways all the time to make it easier to deal with. Meanwhile, we’re clicking right along here on Engineering Works.

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We love numbers

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One, two, three, four … five? For a lot of folks, numbers just don’t add up. That’s too bad, because numbers have a lot to do with why our lives work the way they do. Find out how in today’s Engineering Works.

Unless we’re balancing the checkbook, most of us don’t think much about numbers. They’re just digits on the speedometer or the score in last night’s ballgame. But numbers are the framework our lives are built on. In fact, it’s hard to think of any part of our lives that doesn’t depend on numbers. Just ask an engineer. Numbers are the raw materials of everything engineers do. Let’s take a look.

When the clock radio wakes you up in the morning, the electricity that runs the clock and radio gets there because an electrical engineer used numbers to design the circuits that convert radio waves to music and keep the clock humming in 60-second minutes.

Go into the bathroom to shave or put on makeup. Water flows to your sink because civil engineers measured the size of the pipes needed to carry the wet stuff to your house from the other side of town. Not to mention figuring out where those pipes need to be. That’s numbers, too.

On the way to work, a complex web of numbers calculated by automotive engineers keeps your car rolling down the highway instead of collapsing into a heap of steel, aluminum and plastic. Watch that speed limit!

At work? Well, we won’t even talk about how numbers fit into your computer. It’s enough to make your head hurt. And speaking of numbers and work, don’t forget your paycheck. There’s important numbers there, too. …

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