美国有线新闻 CNN 2013-02-23（在线收听） |
Welcome to CNN student news. Products beingpulled off shelves, authorities running investigations, some shoppersprotesting, all of it has to do with meat. Some packages that were labeled as100% beef were discovered to contain horse meat. Ireland, the UK, France,Germany, Sweden, Switzerland, Romania, the scandal is affecting more than adozen European countries. The latest news is that Nestle, a mega food companyis pulling some of its products in Italy, Spain and France. It's also stoppingdeliveries of some products from a German supplier because traces of horse DNAwere found in the meat. But let's get the big question out of the way, willeating horse meat make you sick? British health officials say, no, the meatitself not a risk, but one concern is about a drug called "Bute",it's used on horses and it can cause some rare but serious health problems forhumans. There is also a religious issue here, somereligions have dietary laws that restrict eating horse meat, since thesepackages were labeled incorrectly, and people might have eaten it withoutknowing. In countries, like France, China and Russia, eating horse meat iscommon. In others, like the United Kingdom, the idea is unthinkable. Would thiskind of thing change your eating of habits? On Twitter, Chris told me, Yes,there are not good circumstances I can think of where I'd willing to eat horse.Matt disagree, "Honestly, I wouldn't change my eating habits just for onesmall chance that I'll eat horse meat."
See if you can ID me? I'm a U.S state thatborders Canada; I have one of America's smallest populations. My southern neighborshares my part of my name and my capital city is Bismarck.
I'm North Dakota, and my name comes from anative American word, for friend.
You might expect North Dakota to gethammered with snow all winter, but on average, the state gets less snow thanthe state to the east or west of it. Then, there is this, a winter stormslammed part of the state last weekend. The I-reporter who sent this video insaid there were four to eight inches of snow and winds blowing through around50 miles per hour. The snow and fog made it harder for driver to see soofficials put out a travel alert. They also warned drivers to watch out forsnow plows that were working to clear the road.
Weather is flying, and flying is weather, apilot named Bob Buck wrote that showing that the two things are always linked.That's why storms like the North Dakota blizzard or the recent nor easter onthe east coast always affect air travel. Flying may still be the safest way totravel, but there is a lot that goes into making it that way. Ayesha Durgaheeshows us what.
"Ladies and gentlemen, I'm,,,from the Atlantics,this is your captain."
And in flight forecast from the front ofthe plane.
"It was cloudy,, I'm and basic ofnortherly winds."
Once the seat bell sign is on, we can getby to enjoy a meal or a movie. Because the planes we fly in are designed tobattle the elements that can suddenly cross that paths.
"There is one lightning strike, everysecond around the world. Every single aircraft is hit by lightning once ayear."
Here, at Cardiff University in Wales, lightningstrikes everyday where capacities discharge a current of 100,000 amps in amicrosecond recreating the power of a lightning bolt at altitude. The aluminumbody of an aircraft is highly conductive, and acts as a Faraday cage. Ametallic shield that directs the electric charge outside towards the back ofthe plane. And passengers on board won't feel a thing.
This 2 million dollar lightening lab inpartnership with EADS and the Welsh government test different conductor stripson the nose of a plane and a new composite material found on modern aircraft.Another built in defense mechanism is using the heat from the engines to meltice around them and along the edge of the wings.
And here at Cardiff University, they havean ice tunnel. Minus ten degrees Celsius with a wind speed of a hundred milesper hour. They can see how ice builds up and understand its aerodynamicqualities.
What we'd find is that generally the icethat forms in this area here can be quite thin, but the ice, which forms alittle bit further back can be a lot thicker which actually reverses thecurvature of the leading edge.
It changes the shape of the wing,essentially.
Quite dramatically, in some cases, yes,unless you do something to prevent it, so in an aircraft, typically we'll workout which part of the aircraft are most critically aerodynamically and thenmake sure that they are protected.
When it comes to aircraft design andweather at research level, there are men and women dedicating their lives tospecific weather conditions to ensure planes are built to buffer and bear theharshest of conditions. And then it's up to the pilots to do the rest. |
| 原文地址：http://www.tingroom.com/lesson/cnn2013/2/233906.html |