Gas from Corn

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Farmers and engineers are getting together to turn corn into fuel you could put into your car’s gas tank. We’ll see how they’re doing, today on Engineering Works!

The idea of using corn as the raw ingredient for alcohol and burning that alcohol in your car or truck is nothing new. Some experts think alcohol – ethanol – could be the future of motor vehicle fuel. Others say it’s not as simple as it sounds.

We grow enough corn to produce lots of alcohol fuel. In fact, we’ll probably distill about five billion gallons this year. That’s about three percent of the gasoline we already use. The problem is that current technology uses lots of fossil fuel – natural gas and coal – to produce the alcohol. Enough that some people say it’s not worth it.

Chemical engineers are working on new ways to distill the alcohol with less fossil fuel, including using parts of the corn plant that’s not used for alcohol to produce a gas kind of like natural gas. We could burn it to provide heat for the distilling process. You can get the same thing by feeding the corn to cows and processing their manure into methane.

So. Will you be going to the – ethanol – station to fill up your car any time soon? We’re getting closer. Lots of cars in Brazil already burn alcohol. And Sweden says they want to replace oil almost entirely with alcohol.

Our gas – alcohol? – tank is full and we’re out of here.

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Crash Barriers

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Today, we’re going to get into the zone – the construction zone – on Engineering Works.

Everybody likes a smooth commute. Nobody likes to see traffic backing up for a construction zone. Even when construction crews are busy repairing or improving roads and streets, we still need to get the kids off to school and get to work ourselves. But it seems like everywhere we drive these days, we run into highway construction.

Well, not exactly. Engineers spend a lot of time and trouble making sure we don’t run into the construction. Portable concrete barriers are one way to keep traffic moving alongside the jackhammers and asphalt spreaders and protect construction workers from wayward vehicles.

For years, these concrete barriers were 32 inches high – about the height of your desk, at work. These barriers worked well for one-way traffic through the work zone. But when you added oncoming traffic, the number of crashes went up.

Here’s why. When the traffic is two-way, drivers pulling out of side roads and driveways couldn’t see over the 32-inch-high barriers. And at night, oncoming headlights were hard to see.

Engineers at the Texas Transportation Institute found that shorter concrete barriers could still do the job. They developed a low-profile design – only 20 inches tall. The shorter height makes oncoming and cross traffic easier to see. The result? Fewer construction zone crashes.

That’s the end of the road for today. See you on down the highway.

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Water Bridge

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People have been building bridges for thousands of years, but there’s never been a bridge quite like a new one in Germany. We’ll check it out, today on Engineering Works!
Think about famous bridges and what do you get? The Golden Gate Bridge. The Brooklyn Bridge. Verrazano-Narrows. If you’re an engineer, you might come up with the Tacoma Narrows bridge. Some are beautiful. Some cross spaces that are especially wide or deep.
The new bridge in Germany is pretty strange. First, instead of pavement, it carries water — over a river. The Elbe River. And instead of cars and trucks, it carries barges, big cargo barges with loads of anything from fuel oil to gravel or grain. This water bridge connects two important canals in central Germany and it lets the barges avoid having to motor along the Elbe River, which can be slow because parts of the river are pretty shallow. Sometimes the water is too low for the barges to move at all.
Building it was a huge project. It’s about half a mile long and deep and wide enough to float barges loaded with 1,500 tons of cargo. Engineers first started thinking about it in 1919. Then World War II and later the Cold War got in the way. But once the German engineers got started, they only spent six years in construction. And $600 million.
Well, our barge is here and it’s time to cross our bridge. See you on the other side.

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Dirty bombs

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We’re going to look into one of the threats that make terrorists terrifying – dirty bombs. Today on Engineering Works!

Only a while ago, terrorism was just a word. Now it’s something everybody knows about — car bombs, hijacked airliners, anthrax in the mail. One of the scariest threats is something called a dirty bomb. Dirty bombs are bombs that scatter radioactive material around where they go off. They’re not nuclear bombs. They’re not weapons of mass destruction. They’re weapons of mass disruption.

Unless you’re near the explosion, your chances of getting seriously hurt by one are pretty small. It’s important to understand that. Dirty bombs are not nuclear bombs. Compared to real nuclear bombs, dirty bombs are firecrackers.

But they are easier to build than nuclear bombs – lots less engineering. That’s what makes them so scary. All you need to make one is some explosives – one stick of dynamite would do for a small one – and radioactive stuff. The most likely stuff is radioactive material hospitals use for nuclear medicine or the radiation sources industry uses for all sorts of things. It’s easy enough to get to be concerned about.

The people in the most danger from a dirty bomb are probably the fire and rescue personnel who treat people injured in the explosion and clean up afterward.

Don’t get us wrong. A dirty bomb is a serious thing. But it’s a long way from a major disaster.

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